01
Start with collected rent
Marketing rent is rarely cash collected over a full year. Vacancy is applied before expenses so the model reflects income you might actually bank.
Real estate underwriting desk
Estimate rental yield before a listing convinces you.
MortarScope converts headline rent into net operating income, yield, and an implied value range. It is built for investors who want a clean first pass before they open a full model.
⭐ 4.7/5 from 312 property users
4,217 yield checks logged in the last 60 days
Works on desktop, tablet, and mobile
Used by acquisition analysts, landlords, and debt advisers who need a faster screen.
Live sample · Midlands terrace
Indicative snapshot
Gross annual rent£23,400
Vacancy-adjusted income£22,230
Net operating income£16,840
Net yield at £298,0005.65%
Target yield5.90%
Indicative value£285,424
A small change in vacancy and repairs can narrow the price you should pay by five figures. That is why the screen starts with operating assumptions, not marketing copy.
Tool 1
Rental yield and indicative value calculator
Enter rent, vacancy, operating costs, and your target yield. The model returns gross yield, net operating income, net yield, and the value that matches your yield requirement.
Gross annual rent£0
Effective income after vacancy£0
Management cost£0
Net operating income£0
Gross yield0%
Net yield0%
Indicative value at target yield£0
Method
How MortarScope approaches the first screen
The goal is not to replace due diligence. It is to prevent weak deals from getting further than they deserve.
02
Remove operating drag
Management, repairs, and recurring ownership costs compress yield faster than most listing summaries admit. The calculator keeps them visible in one place.
03
Translate yield into value
If your net yield threshold is fixed, a fair price falls out of the operating income. That number is often calmer than the asking price.
Journal
Recent notes from the MortarScope desk
Yield
Why a cap rate without operating detail is only half a sentence
A practical look at the places where investors quietly lose basis points long before a deal reaches completion.
By Amelia Trent · March 2026
Read →Debt
Mortgage stress assumptions that still matter when rates stop moving
Cashflow can soften even in a flat-rate market when amortisation, insurance, and tax buffers are ignored.
By Nathan Ivers · March 2026
Read →Valuation
When a tidy refurbishment lifts rent but not investment value
Improvement spend can look productive on a viewing while leaving exit value almost unchanged under a disciplined yield test.
By Clara Wren · March 2026
Read →Field notes
What users say after replacing rough spreadsheets
These comments come from people using the site at the screening stage, not after a polished investment memo has already been written.
★★★★★
“I use MortarScope before broker calls. It saves me from discussing stock that cannot support my minimum yield once repairs are priced honestly.”
Hannah Reeves · Buy-to-let investor, Leeds
★★★★★
“The indicative value output is useful when agents talk in vague comparables. It gives me a disciplined anchor before emotion takes over.”
Julian Mercer · Acquisition associate, Bristol
★★★★☆
“Our lending team uses it for a first conversation with novice landlords. The split between vacancy and operating costs makes weak deals obvious.”
Sophie Kent · Mortgage adviser, Kent
FAQ
Questions investors ask most often
These answers cover screening logic rather than local tax or legal advice.
Should I model vacancy even in a tight rental market?
Yes. Tight supply reduces downtime, but it does not remove reletting friction, maintenance gaps, or periods when rent collection slips.
Does the calculator include financing?
No. Tool one isolates property performance before debt so you can judge the asset on its own economics.
What operating costs belong in the annual expense figure?
Use recurring ownership costs such as insurance, planned repairs, service charges, compliance, and routine admin that are not already included in management fees.
Why is the indicative value lower than market comparables?
If your target yield is stricter than the local market norm, the price your model supports will usually sit below aspirational asking levels.
Can this be used for blocks or mixed-use stock?
Yes, as a first pass. For larger assets, group costs carefully and confirm whether income should be modelled unit by unit.
How often should I revisit my target yield?
Whenever debt pricing, local rent growth, or exit liquidity changes. A threshold set six months ago may no longer match present risk.