A side-by-side comparison of putting Dad's ~£270k compulsory-purchase proceeds into a shared £500k home versus keeping it invested and renting. Figures are illustrative and rounded — confirm with a solicitor, tax adviser and mortgage broker before acting.
For retired parents who want a permanent home, buying is usually the better fit — provided the mortgage is genuinely affordable for your sister over the long term. Two things tip it beyond the money: security of tenure (no landlord can move elderly parents on) and a legitimate care-fee shelter — Dad's £270k held as cash is 100% assessable in a care means-test, but the same money held as a share of the home he lives in is disregarded for as long as Mum lives there.
The counter-intuitive catch: renting is actually cheaper month-to-month (the £270k throws off income and there's no maintenance or mortgage interest), and it keeps the capital liquid and flexible. Buying costs more each month but converts that cash into a £350k–£665k asset over ten years via mortgage leverage. So the real question isn't "which is cheaper this year" — it's "do you value a secure, appreciating, care-sheltered home more than liquidity and flexibility?"
Dad £270k + Sister £36k + £202k mortgage. Structured so Dad keeps a protected share (see care/tax note below).
Dad's £270k spread across ISA / Premium Bonds / fixed & easy-access at a ~4.5% blend; the household rents.
The monthly housing cost is broadly similar either way, so the honest differentiator is what you own at the end. Buying's outcome swings on house-price growth; renting's capital is roughly flat in nominal terms (interest is spent on rent). Forecasts for 2026–29 cluster around 1–4% a year.
| After 10 years | Buy · prices flat (0%/yr) | Buy · +3%/yr | Buy · +5%/yr | Invest & Rent |
|---|---|---|---|---|
| Home value | £500,000 | £671,958 | £814,447 | — |
| Mortgage remaining | £149,338 | £149,338 | £149,338 | — |
| Home equity owned | £350,662 | £522,620 | £665,109 | — |
| Liquid capital retained | — | — | — | £306,000 |
| Net asset position | £350,662 | £522,620 | £665,109 | £306,000 |
Assumes £202k mortgage at 5% over 25 years, £306k of family cash into the home, and interest income in the rent case spent on rent (so capital stays ~flat in nominal terms — worth ~£228k in real 2026 money after a decade of inflation). Even with flat house prices, buying edges ahead on assets; a fall in prices is the scenario where renting wins.
| Factor | Buy | Invest & Rent |
|---|---|---|
| Security of tenure for retired parents | Strong — it's their home | Weak — landlord/rent risk, forced moves |
| Care means-test (Dad's £270k) | Sheltered — home disregarded while Mum lives there | Fully assessable as cash (limit £23,250) |
| Liquidity & flexibility | Illiquid; costly to exit | Fully liquid; easy to move |
| Burden on Sister | 25-year mortgage early in her career | No mortgage commitment |
| Deprivation of assets (care) | Fine — Dad keeps his capital as equity | Fine — Dad keeps his capital as cash |
| Inflation protection | Home value tends to track/beat inflation | Cash erodes in real terms |
| Exposure to a house-price fall | Yes — leveraged downside | None |
The buy case only works safely if Dad's contribution and his right to live there are locked down. The full breakdown of gift vs loan vs co-ownership vs trust is on the Transferring Dad's money page. Take these to a solicitor:
Important: This is background research to frame a family decision, not regulated financial, tax or legal advice. All figures are illustrative, rounded, and depend on the actual price, mortgage terms, rates and Dad's pension income. Verify everything with qualified professionals before acting.
Key sources: SDLT & first-time-buyer relief 2026 · HMRC pre-owned assets manual · IHT nil-rate bands frozen to 2031 · UK house-price forecasts 2026 · Mortgage-rate outlook 2026 · Care means-test & home disregard · Deprivation of assets
Prepared 14 July 2026 · England (SDLT / care rules) · illustrative model.