PropertyScout guides
How to analyse a UK buy-to-let deal
A good buy-to-let read is not just about gross yield. It is about whether the rent is real, the works are believable, and the downside still makes sense once buying costs and drag are included.
Worked example · illustrative figures
A £180,000 rental, after the obvious costs
Illustrative monthly scenario: £1,100 rent, 75% borrowing at 5.5% interest-only. Allow 10% management, 6% maintenance, 5% vacancy and £40 other costs. Buying costs, works and tax need separate checks.
| Item | Example | Basis / comparison |
|---|---|---|
| Rent | £1,100 | An assumption to verify |
| Mortgage interest | £618.75 | £135,000 × 5.5% ÷ 12 |
| Management, maintenance and vacancy | £231 | 21% of gross rent |
| Other costs | £40 | Illustrative allowance |
| Monthly cashflow before tax | £210.25 | Rent less the costs above |
Gross yield is 7.33%, but the monthly surplus in this example is £210.25 before tax. A vacancy or an unexpected bill can change the result.
Test a rental scenarioWhat would make this buy-to-let worth progressing at all?
The first pass should answer a hard question: if this deal works, why does it work? Usually that comes down to one of three things: genuine rent support, a price position below the local sold picture, or a low-friction asset that does not need heroic intervention.
- Write the deal thesis in one line before you touch the calculator.
- Treat the asking price as context, not as proof that the opportunity is cheap.
- Decide early whether this is meant to be a yield play, a stability play, or a value-add play.
Do not trust the deal until the rent stack makes sense
Most weak buy-to-let reads break on rent. The right order is evidence-backed rent, then comparable-backed rent, then modelled rent only as context. If the rent is thin, the deal is still a lead, not a conclusion.
- Prefer agent-stated passing rent or live rental evidence over broad local averages.
- Check whether the comparable stock really matches condition, size, and micro-location.
- If rent is still modelled, label it clearly and stay cautious until better evidence lands.
This is where a lot of false confidence comes from. Thin rent support should directly soften the recommendation.
Yield, cashflow, and costs need to agree with each other
Once rent is believable, combine it with buying costs, finance drag, expected works, management friction, and any obvious compliance spend. Gross yield alone can still flatter a deal that becomes mediocre once the real stack is loaded in.
- Run both gross and net yield, then check whether monthly cashflow still earns the effort.
- Separate unavoidable buying costs from optional improvement spend.
- Ask whether the current numbers still work if rent slips or works come in above the first pass.
End with a next move that someone else could follow
A serious buy-to-let memo should finish with a decision state and a next move. That might be shortlist, reject, or hold for evidence. If someone else cannot pick it up and act on it, the analysis is not finished.
- State what supports the case, what still needs proving, and what happens next.
- Keep the recommendation honest when rent, EPC, or sold evidence is still proxy-backed.
- Use a Deal Pack when the output needs to leave your desk and hold up under scrutiny.
What is the biggest mistake in buy-to-let analysis?
Treating a headline yield as if it settles the decision. Weak rent support, underestimated works, and ignored buying costs can all make a seemingly strong gross yield much less attractive in practice.
When is modelled rent acceptable?
Modelled rent is useful for screening, but it should be treated as provisional. Real confidence should come from agent-stated rent, passing income, or direct comparable evidence wherever possible.
What should happen before a serious offer?
Confirm rent evidence, check sold support, tighten the works view, and make sure the next move is explicit. That is the point where the deal stops being a hopeful listing read and starts becoming a real buying case.
Your next move
Give your property search
a clearer direction.
No card required. Start with Free.