About
Rent / Buy / Invest is a private UK decision sketchpad for comparing renting, buying (including shared ownership), and investing. It’s built to reduce noise and make trade‑offs visible, without asking for sign‑ups or personal data.
Start with monthly cost + cash to move — it’s the fastest reality check
- Monthly cost (what leaves your account) in each scenario.
- Cash to move (deposit, fees, tax) so affordability is checked early.
- What you burn: rent + mortgage interest, so you can compare the two kinds of “money gone”.
- Quick stress test to see sensitivity to income and rates.
Shared ownership is not binary — compare rent burned vs interest burned, and model staircasing timing
- You often pay rent on the part you don’t own and a mortgage on the part you do. Staircasing shifts that mix over time.
- This tool surfaces rent burned and interest burned in the same place, so you can compare them directly.
- Future staircasing steps are separate scenarios, so you can see the impact of when you do it (not just the headline %).
Know what you’re actually borrowing — deposit down, new mortgage up (fees included if added to the loan)
- For each future step, you can see the new mortgage borrowed (principal) separately from the total mortgage balance.
- Product fees can be modelled as cash or added to the mortgage — and the tool can spread fees over the intro period to show an effective rate.
Model scenarios side‑by‑side — “staircase first” vs “buy later” without rewriting everything
- Renting (market rent) as a baseline.
- Shared ownership: rent on the unsold share, service charge, staircasing, and “sell & buy”.
- Buying: repayment vs interest‑only, product fees, and refix assumptions.
- Investing the difference: what happens if you keep renting (or buy later) and invest monthly instead.
How to use it (4 steps) — even if you have no finance background
- Start in Current circumstances and enter only what you know (income, rent/service charge, property value, mortgage balance/rate if you have one).
- Add a future scenario and set Mortgage start as “months from now” (e.g., 9 or 24).
- Use Essentials (and pinned rows) to keep the few rows you care about and reduce scroll.
- Stress‑test your assumptions, then refine numbers as you learn more.
Privacy-first by design — runs locally, no sign‑in, no tracking
- No sign‑in, no tracking, no ads.
- Runs locally in your browser; you can export/import a CSV backup if you want portability.
- Built to help you think clearly, not to sell you a product.
Not financial advice
This is an educational calculator. It is not financial advice and it does not recommend or arrange mortgages, investments, or tax treatment. Results are indicative and depend on assumptions. You are responsible for decisions and outcomes. If you need regulated advice, speak to an FCA‑authorised adviser. Fees and taxes are estimated and simplified — verify with official sources before acting.