RentalBux vs. KEYinfinity (Landmark)
Which MTD Software Is Better for UK Landlords?
Overall Winner: RentalBux
RentalBux is the better MTD software for UK landlords. It combines full Making Tax Digital compliance across UK property income, foreign property income, and self-employment income with comprehensive property management, automated bookkeeping, AI-driven expense categorisation, joint ownership profit-splitting, and a free plan for single-property landlords until March 2028 — all in a single, cloud-native platform with native iOS and Android apps. KEYinfinity is a well-developed, HMRC-recognised cloud accounting platform from Landmark Systems — a trusted name in UK rural business software backed by nearly 40 years of experience and investment from ISAGRI, a global leader in agricultural software. It offers real-time cashflow reporting, direct bank feeds, a fixed asset module, invoice recognition, and VAT and MTD Income Tax compliance. But KEYinfinity is fundamentally a farm and rural business accounting tool. It does not include property management features, has no landlord-specific functionality, requires accounting knowledge to configure, and is priced on a quote basis without a published free tier. For residential, HMO, buy-to-let, and mixed-income landlords, RentalBux is the purpose-built, more accessible choice.
At-a-Glance MTD Software Comparison
Key differences between RentalBux and KEYInfinity (Landmark) across MTD compliance, property management, bookkeeping, pricing, and landlord-specific features.
| Feature | RentalBux | KEYInfinity (Landmark) |
|---|---|---|
| Software Type | Property/Landlord Platform | Cloud Farm & Rural Business Accounting |
| Target Users | Landlords, Sole Traders, Letting Agents | Farms, Rural Estates, Agricultural Businesses, Rural Accountants |
| Income Sources Supported | Sole Trader + UK Property + Foreign Property | UK Business + Property income (rural/agricultural focus) |
| Free MTD Software Plan | Free until March 2028 (1 property) | No |
| MTD Quarterly Updates to HMRC | Yes | Yes |
| Final Declaration | Yes | Yes |
| Bank Reconciliation | Yes | Yes |
| Automated Bank Feeds | Yes | Yes |
| Invoice Creation | Yes | Yes |
| Receipt Capture (OCR) | Yes | Yes |
| Expense Auto-Categorisation | Coming soon | No |
| Property Portfolio Management | Yes | No |
| Tenant Management | Yes | No |
| Joint Ownership & Profit Sharing | Yes | No |
| Payroll | No | No |
| HMO Unit-Level Tracking | Yes | No |
| HMRC SA105 Box Pre-Mapping | Yes | No |
| Spreadsheet Import/Export | Yes | Yes |
| Platform | Web, iOS, Android | Web browser only |
| GDPR Compliant | Yes | Yes |
What Is RentalBux? What Is KEYinfinity (Landmark)?
What Is RentalBux?
All-in-One MTD Software for Landlords and Sole Traders
RentalBux is an all-in-one property management, accounting, and Making Tax Digital compliance platform built specifically for UK landlords, letting agents, and self-employed individuals. Designed with direct input from accountants who specialise in property and sole trader tax, RentalBux covers everything from tenancy management and rent collection to full bookkeeping with a pre-configured chart of accounts tailored to the property sector.
RentalBux is fully HMRC-recognised for Making Tax Digital for Income Tax across all three qualifying income categories: UK property income, foreign property income, and self-employment. This makes it one of the only landlord-specific MTD software platforms that can handle a landlord who also runs a sole trader business, all from a single subscription.
A major differentiator is RentalBux's pricing model: single-property landlords can use the platform completely free until March 2028, making it one of the most affordable HMRC-approved MTD software options for landlords entering the MTD regime.
What Is KEYInfinity (Landmark) ?
KEYinfinity, your anywhere, anytime farm accounting solution
KEYinfinity is the cloud-based accounting software from Landmark Systems Ltd, a UK company headquartered in Pulborough, West Sussex, with nearly 40 years of experience serving rural businesses. It is the cloud counterpart to Landmark's established KEYPrime Accounts range, built on a modern, web-based architecture accessible from any device with an internet connection. KEYinfinity is backed by ISAGRI, a global leader in agricultural software, which provides ongoing investment in its development and long-term platform sustainability.
KEYinfinity is HMRC-recognised for both MTD for VAT and MTD for Income Tax, offering quarterly updates and the final declaration for eligible taxpayers. The platform is tailored specifically for farms, rural estates, and diversified rural businesses — using familiar rural terminology and workflows. Key features include real-time cashflow reporting, direct bank feeds via TrueLayer (FCA-regulated), invoice recognition (50 scans per month standard, with an enhanced plan for 500 scans/year at £20), full VAT management, invoicing, budgeting with copy functionality, a fixed assets module with depreciation, a stocks module, recurring entries, and date blocking controls added in KEYinfinity 2.0.
Strengths
- Free MTD software for single-property landlords until March 2028
- Handles sole trader + UK property + foreign property income in one platform
- Joint ownership with automatic profit-sharing split by ownership percentage
- Pre-built chart of accounts tailored for landlords and sole traders
- AI-powered expense auto-categorisation and OCR receipt capture
- Agent filing on behalf of landlords — ideal for accountants and letting agents
- Supports HMO properties with auto-created units
Strengths
- HMRC-recognised for MTD VAT and MTD Income Tax
- Cloud-native, accessible from any device with internet access
- Real-time cashflow reporting and enterprise analysis
- Direct bank feeds via TrueLayer (FCA-regulated)
- Invoice recognition (50 scans/month standard)
- Fixed assets module with depreciation (added v2.0)
- Stocks module and inventory valuation
- Recurring entries for frequent transactions (v2.0)
- Date blocking controls to protect closed periods (v2.0)
- Budget copy functionality for faster forecasting (v2.0)
- Backed by ISAGRI — global agricultural software leader
- Accountant/consultant access from anywhere
- UK-based support and training from Landmark
- Royal Warrant holder (Landmark Systems)
Limitations
- Newer to market compared to established platforms
- No yield or LTV investment analysis tools
- No MTD for VAT support yet
- Some advanced reporting features still in development
- Limited third-party app integrations
- No offline capability
- No tax liability forecasting feature currently
Limitations
- No property management features — accounting only
- No native iOS or Android mobile app
- Pricing not published — requires sales consultation
- No joint ownership or profit-splitting functionality
- Foreign property income MTD not confirmed
- Designed for rural businesses — not landlord-specific
- No compliance document alerts, HMO support, or tenant management
- No AI-powered expense auto-categorisation
- No free tier or listed free trial
- Requires accounting knowledge to configure effectively
- No confirmed property module integration (unlike KEYPrime Accounts)
- Relatively new cloud platform — evolving feature set
- No mileage tracking
- Offline working not available (cloud only)
Making Tax Digital Compliance
How RentalBux Handles MTD Compliance
RentalBux supports all three MTD qualifying income categories: sole trader income, UK property income, and foreign property income. This makes it suitable for landlords who also earn self-employment income, eliminating the need for separate software. Most accounts are pre-mapped to HMRC Self-Assessment boxes. RentalBux also supports agent filing, allowing accountants or letting agents to submit MTD returns on behalf of their landlord clients.
How KEYinfinity Handles MTD for Landlords and Sole Traders
KEYinfinity is HMRC-recognised for MTD for Income Tax and supports quarterly updates and the final declaration. Landmark's website explicitly states the product is "HMRC Approved for MTD for IT" on the KEYinfinity product page. MTD VAT submissions have been supported across the Landmark range since 2019. The MTD Income Tax workflow in KEYinfinity requires the user to connect to HMRC via their Government Gateway credentials and map income and expenditure nominals to appropriate Self Assessment categories — the same process used in KEYPrime Accounts v14.5+.
| Feature | RentalBux | KEYInfinity (Landmark) |
|---|---|---|
| HMRC Recognised (MTD ITSA) | Yes | Yes |
| MTD Quarterly Updates | Yes | Yes |
| Final Declaration | Yes | Yes |
| Digital Record Keeping | Yes | Yes |
| Digital Links Compliant | Yes | Yes |
| Sole Trader Income | Yes | Yes |
| UK Property Income | Yes | Yes |
| Foreign Property Income | Yes | No |
| Multiple Income Streams | Yes | No |
| Agent Filing on Behalf | Yes | Yes |
Winner: RentalBux — Confirmed foreign property income support, pre-mapped SA boxes requiring zero manual configuration, a free plan covering full MTD compliance, and a landlord-specific workflow give RentalBux the decisive advantage. KEYinfinity provides solid HMRC-recognised MTD compliance for rural business income, but its landlord suitability for property-specific MTD workflows — particularly foreign property and the absence of a property management module — is more limited.
Property Management
RentalBux: Property Management
RentalBux provides comprehensive property portfolio management with tenant management, rent tracking, property expense allocation, and support for multiple properties. A standout feature is its joint ownership and profit-sharing capability: landlords can define ownership percentages once, and RentalBux automatically splits rental income and expenses. RentalBux also supports HMO properties, automatically creating individual units.
KEYinfinity: Accounting Only — No Property Management
KEYinfinity does not include property portfolio management, tenant management, rent demand generation, service charge management, compliance date reminders, mortgage tracking, or any other landlord-specific operational features. Its focus is entirely on business accounting — invoicing, expense management, bank reconciliation, VAT returns, and MTD submissions. Rural estate clients requiring property management alongside KEYinfinity accounting would need to manage property operations separately or explore the KEYPrime Property product in conjunction with KEYPrime Accounts.
| Feature | RentalBux | KEYInfinity (Landmark) |
|---|---|---|
| Property Portfolio Management | Yes | No |
| Tenant Management | Yes | No |
| Rent Tracking | Yes | No |
| Property Expense Allocation | Yes | No |
| Multiple Property Support | Yes | No |
| HMO Property Support | Yes (auto-creates units) | No |
| Joint Ownership/Profit Sharing | Yes (auto-split by %) | No |
| Maintenance Tracking | No | No |
| Tenant Screening | No | No |
| Compliance Document Alerts | Yes | No |
| Arrears Tracking | No | No |
Winner: RentalBux — KEYinfinity offers no landlord-specific property management features. RentalBux wins outright on every property management dimension relevant to UK landlords.
Bookkeeping, Accounting & Digital Record Keeping
RentalBux: Structured Accounting
RentalBux includes a pre-built chart of accounts specifically designed for landlords and sole traders, covering rental income, mortgage interest, insurance, property repairs, professional services, utilities, and tenant deposits. All accounts are pre-mapped to HMRC Self-Assessment boxes. The platform supports cash basis accounting, bank reconciliation, and journal entries.
KEYinfinity: Full Cloud Accounting for Rural Businesses
KEYinfinity provides a comprehensive cloud accounting environment with full double-entry bookkeeping, customisable chart of accounts with rural business terminology, bank feeds via TrueLayer (FCA-regulated open banking), invoice recognition for automated data capture, VAT management, budgeting, and formal financial reports including cashflow statements. KEYinfinity 2.0 introduced several significant additions: a fixed asset module with straight-line and reducing balance depreciation, a stocks module for inventory valuation, recurring entries for sales invoices, purchase invoices, bank payments, and bank receipts, date blocking controls to prevent posting errors in closed periods, and budget copy functionality for faster forecasting.
| Feature | RentalBux | KEYInfinity (Landmark) |
|---|---|---|
| Cash Basis Accounting | Yes | Yes |
| Chart of Accounts (Pre-built, Landlord-Tailored) | Yes (pre-built + custom) | Yes |
| Journal Entries | Yes | Yes |
| Bank Reconciliation | Yes | Yes |
| Automated Bank Feeds | Yes (Major UK banks) | Yes |
| Open Banking Integration | Yes | Yes |
| Double-Entry Bookkeeping | Yes | Yes |
| HMRC Box Pre-Mapping | Yes | No |
| Xero Integration | No | No |
| Spreadsheet Import/Export | Yes | Yes |
| Digital Record Storage | Yes | Yes |
Winner: KEYinfinity on accounting depth and business tools; RentalBux on landlord accessibility and pre-configuration — KEYinfinity's fixed assets, stocks, recurring entries, date blocking, and advanced budgeting make it a more complete accounting platform for complex rural businesses. RentalBux wins on pre-mapped landlord accounts and expense auto-categorisation, which require no setup and no accounting knowledge.
Invoicing, Expense Tracking
RentalBux: Expense Management
RentalBux includes OCR receipt capture, structured expense tracking with landlord-specific categories, auto-categorisation, invoice creation with customisable branding, and payment tracking with reminders.
KEYinfinity: Invoice Recognition and Rural Business Expense Management
KEYinfinity's invoice recognition tool extracts data from uploaded invoices and bills, reducing manual data entry for rural businesses with regular supplier invoice flows. With the 2.0 update, recurring entries allow users to set up templates for frequently used transactions — a significant time-saver for farms with regular fixed payments. Bank feeds from TrueLayer streamline bank reconciliation. However, KEYinfinity does not offer AI auto-categorisation of expenses in the way that RentalBux does — expense categorisation remains a manual task once transactions are imported, with invoice recognition providing the data capture layer rather than automatic categorisation logic.
| Feature | RentalBux | KEYInfinity (Landmark) |
|---|---|---|
| Invoice Creation & Sending | Yes | Yes |
| Invoice Customisation/Branding | Yes | No |
| Online Payment Collection | Yes | No |
| Payment Tracking/Reminders | Yes | Yes |
| Expense Tracking | Yes | Yes |
| Receipt Capture (OCR/Photo) | Yes | Yes |
| Expense Categorisation | Yes | Yes |
| Automated Transaction Matching | Yes | Yes |
| Mileage Tracking | No | No |
| AI Auto-Categorisation | Coming soon | No |
Winner: RentalBux wins on AI auto-categorisation, landlord-specific expense categories, and payment tracking for rent. It also provides invoice customisation & branding, and online payment collection.
Reporting & Tax Forecasting
RentalBux: Formal Accounting Reports
RentalBux produces structured financial reports including profit & loss statements, balance sheets, journal reports, ledger reports, and trial balances. Smart categorisation helps ensure accuracy.
KEYinfinity: Real-Time Rural Business Reporting
KEYinfinity's reporting suite centres on real-time cashflow reporting — giving farm and rural business owners an up-to-date picture of their financial position without waiting for end-of-period processing. It also produces profit & loss, balance sheet, and enterprise analysis reports. The budget copy functionality introduced in v2.0 enables more efficient financial planning by building new forecasts from prior-year data. Tax forecasting is not listed as a feature.
| Feature | RentalBux | KEYInfinity (Landmark) |
|---|---|---|
| Profit & Loss Report | Yes (formal) | Yes |
| Balance Sheet | Yes | Yes |
| Trial Balance | Yes | Yes |
| Dashboard/Overview | Yes | Yes |
| Real-Time Financial Data | Yes | Yes |
| Cash Flow Reporting | No | Yes |
| Tax Estimate/Forecast | Yes | No |
| AI-Powered Features | Coming soon | No |
Winner: Tie — RentalBux leads on property-level reporting. It also offers tax forecasting. KEYinfinity leads on cashflow reporting, enterprise analysis, and budget forecasting for rural businesses.
Collaboration & Mobile Apps
RentalBux's Collaborative Features
RentalBux enables agent filing, which gives accountants and letting agents the ability to submit directly on a landlord's behalf.
KEYinfinity's Collaborative Features
KEYinfinity's cloud-native architecture means accountants and consultants can log in and access client data from anywhere — an advantage over the PC-based KEYPrime Accounts, which requires remote desktop or a hosted server for off-site access. Landmark offers accountant and consultant licences to support practices managing rural clients. UK-based telephone support and structured training are available to all KEYinfinity users. The ISAGRI backing provides ongoing development investment and the long-term platform assurance that comes with a globally scaled agricultural software group. Landmark Systems itself holds a Royal Warrant, and is the NFU's sole recommended farm software supplier — credentials that carry significant trust within the rural sector.
| Feature | RentalBux | KEYInfinity (Landmark) |
|---|---|---|
| Accountant/Advisor Portal | Yes | Yes |
| Multi-User Access | Yes | Yes |
| Agent Filing on Behalf | Yes | Yes |
| Bank Integration | Yes | Yes |
| Platform | iOS, Android | Web browser only |
| Web Browser Access | Yes | Yes |
| FCA Regulated | Yes | Yes |
| GDPR Compliant | Yes | Yes |
Winner: RentalBux for mobile and landlord-specific collaboration. RentalBux wins on native mobile apps, property-level accountant access, and agent filing tailored to landlord portfolios.
Ease of Use, Support & Security
RentalBux: Guided Workflows
RentalBux uses guided workflows, clear dashboards, and no accounting jargon. The platform offers phone support, email/chat support, and a help centre with guides and knowledge base articles.
KEYinfinity's Ease of Use
KEYinfinity is a cloud accounting system designed for rural business users and their accountants. Customer testimonials describe it as "clear, easy to use, and designed with the needs of farms in mind." Landmark's support team is described consistently as "second to none" across testimonials from farm secretaries, bookkeepers, and rural accountants. UK-based telephone support is available alongside remote support and structured training. Landmark's support team is described in independent testimonials on the Landmark website as consistently professional, efficient, and kind. Landmark holds a Royal Warrant and is the NFU's sole recommended farm software supplier — a measure of both quality and sector trust. Both platforms are GDPR-compliant and use FCA-regulated open banking providers for bank feed connectivity.
| Feature | RentalBux | KEYInfinity (Landmark) |
|---|---|---|
| Phone Support | Yes | Yes |
| Chat Support | Yes | Yes |
| Email Support | Yes | Yes |
| Help Centre/Knowledge Base | Yes | Yes |
| FCA Regulated | Yes | Yes |
| Enterprise-Grade Security | Yes | No |
RentalBux Features
Sole Trader Income Support for MTD
RentalBux is one of the few landlord-focused MTD software platforms that supports self-employment income alongside UK and foreign property income within a single account. Landlords who also run a trade, consultancy, or freelance business can manage all quarterly submissions from one dashboard. Landlord Studio covers property income only.
Custom Chart of Accounts for Landlords
A property-tailored chart of accounts covering rental income, mortgage interest, insurance, repairs, utilities, letting agent fees, and more — all pre-mapped to HMRC Self-Assessment boxes. No setup required; the system is ready to use from day one. Landlord Studio has no equivalent.
Agent Filing on Behalf of Landlords
Letting agents and accountants can submit MTD quarterly updates and the Final Declaration on behalf of landlord clients directly from the platform. Landlord Studio allows accountant access but does not support submission on the landlord's behalf.
Branded Invoice Creation
Invoice creation with customisable branding for service charges and commercial landlords. Not available in Landlord Studio.
AI-Powered OCR Receipt Capture with Auto-Categorisation (Coming soon)
RentalBux's AI will read uploaded receipts and categorise the expense automatically against the pre-built chart of accounts. Landlord Studio's Smart Scan extracts dates and amounts but does not include AI-driven expense categorisation.
Formal Accounting Reports
Balance sheet, trial balance, ledger reports, and journal reports. Landlord Studio does not produce these natively.
Free Plan Including MTD Submissions Until March 2028
RentalBux's free single-property plan includes MTD quarterly submissions. Landlord Studio's free GO plan covers property management for up to three units but requires a paid PRO plan (from £12/month) to access MTD submission functionality.
Unique Features Only KEYinfinity Offers
Fixed Asset Module with Depreciation
Track asset purchases and movements, and automatically calculate depreciation using straight-line or reducing balance methods — essential for farms and rural businesses with significant equipment and capital assets.
Stocks Module and Inventory Valuation
Record and update stock valuations for end-of-year accounts and improved visibility of inventory across the business.
Recurring Entries
Set up templates for frequently used transactions including sales invoices, purchase invoices, bank payments, and receipts — processing regular transactions quickly and consistently.
Date Blocking Controls
Prevent users from posting transactions before a defined date, protecting the integrity of closed accounting periods.
Budget Copy Functionality
Copy existing budgets to build new forecasts from prior-year data, significantly reducing setup time for financial planning.
Enterprise Analysis and Rural Business Reporting
Enterprise-level financial analysis designed around the terminology and reporting needs of farms and diversified rural businesses.
ISAGRI Backing and Long-Term Investment
KEYinfinity is backed by ISAGRI, a global leader in agricultural software, providing ongoing development investment and platform sustainability. This gives users confidence in KEYinfinity's long-term roadmap and the financial strength behind its continued development.
Invoice Recognition with Enhanced Volume Option
50 scans per month as standard, with an enhanced plan of 500 scans per year available at £20 — a cost-effective document capture option for rural businesses with regular supplier invoice flows.
Who Should Choose RentalBux?
RentalBux is a strong fit if you:
Landlords with Mixed Income Streams
If you earn from both property and self-employment, RentalBux handles sole trader income alongside UK and foreign property income in a single MTD-compliant platform.
Joint Owners and Family Portfolios
The automated profit-sharing split is a standout feature. Define ownership percentages once and RentalBux calculates each owner's share automatically.
Budget-Conscious Landlords Entering MTD
Free MTD software for single-property landlords until March 2028, with no upfront commitment.
Landlords Who Want Proper Accounting Structure
Chart of accounts, journal entries, profit & loss, balance sheet, and trial balance give RentalBux a structured accounting foundation.
Accountants and Letting Agents
Agent filing on behalf, multi-user access, and spreadsheet import make RentalBux practical for professionals managing multiple landlord portfolios.
Commercial Landlords and HMO Owners
Invoice creation with branding for service charges, plus automatic HMO unit creation and tenant management.
Who Should Choose KEYinfinity (Landmark)?
KEYinfinity is the better choice for:
Farms and Rural Businesses Already in the Landmark Ecosystem
If your business already uses Landmark software for crop management, livestock, or KEYPrime Accounts, KEYinfinity provides a modern cloud accounting pathway with the same Landmark quality and support — an upgrade without changing provider.
Rural Businesses Wanting a Cloud Accounting Platform with Sector-Specific Terminology
KEYinfinity is built with the vocabulary and workflows of rural businesses in mind, making it more intuitive for farm secretaries, estate bookkeepers, and rural accountants than generic cloud accounting platforms.
Rural Accountants and Consultants Managing Multiple Farm or Estate Clients
Cloud-based access from anywhere, accountant licences, and Landmark's sector expertise make KEYinfinity a strong choice for rural accounting practices.
Businesses with Complex Asset and Inventory Needs
The fixed assets module, stocks module, recurring entries, and date blocking controls make KEYinfinity more appropriate than RentalBux for businesses with significant capital equipment, regular depreciation requirements, and high invoice volumes.
Agricultural Landlords and Diversified Rural Estates Already Using KEYinfinity for Farm Accounts
Where a rural estate manages farmland alongside rental properties and already uses KEYinfinity for farm accounting, the consistent reporting environment and shared bank feeds add operational efficiency.