OpenProp/Guides/Rent vs Buy: 10 Queries to Know If Buying Is Actually Possible
Guide
Rent vs Buy: 10 Queries to Know If Buying Is Actually Possible
2026-04-176 min readData from HM Land Registry
Your situation: You've been paying rent for years and wonder whether buying is realistic — or something that keeps moving further away. This guide uses real Land Registry data to give you a concrete answer, and an interactive calculator to show whether your numbers work.
Step 1 — Find Out What Entry Level Costs in Your Target Borough
Start with the lower quartile price — not the median. The lower quartile is the price at which 25% of flats sold for less. It's the realistic floor for a first buyer, not an estate agent's showcase number.
Ask the bot for your target borough first. Then run the same query for any others you're considering.
Query 1 of 10
"What is the lower quartile flat price in Tower Hamlets?"
Run this once for each borough you're weighing up. The bot answers one borough at a time — ask separately for Lewisham, Waltham Forest, or whichever others are on your list.
✓ Real data — HM Land Registry, current to Feb 2026
These are completed sale prices — what buyers actually paid, registered with HM Land Registry. Tower Hamlets' lower quartile (£365,000) reflects the Canary Wharf / Bow area — a large, active flat market with good transport links.
Step 2 — Run the Rent vs Buy Calculator
Now put your own numbers in. This tells you how long it takes to save your deposit, what your mortgage will cost, and whether buying is cheaper than renting month-to-month.
Quick Rent vs Buy Calculator
🏠 Your Rent
£/mo
💰 Your Savings
£/yr
£/mo
% p.a.
🏡 Your Target Property
£
%
🏦 Your Mortgage
% p.a.
Deposit needed
—
—
Time to save deposit
—
with compound savings interest
Rent paid while saving
—
money that won't come back
Monthly mortgage (25 yr)
—
—
Buying vs renting monthly
—
—
Income-based max mortgage
—
rough rule: income × 4.5
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How to use this: Set the property price to the lower quartile figure you got from the bot. Change the deposit % to see how much faster you can buy with 5% vs waiting for 10%. Adjust the savings rate to see how much a cash ISA helps.
"How has the median flat price in Tower Hamlets changed over the last 5 years?"
If prices rose 40% while you were renting and saving, the deposit target kept moving up. If prices fell or stayed flat, you haven't lost ground.
✓ Real data — HM Land Registry 2021–2025
Median Flat Price — Tower Hamlets
2021 (peak)
£539,000
2022
£500,000
2023
£470,000
2024
£465,000
2025
£455,000
Tower Hamlets flat prices have fallen −15.6% from their 2021 peak of £539,000. The lower quartile — your entry point — has also fallen, from £407,545 in 2021 to £365,000 in 2025. Every year you've been renting and saving, the entry price has actually come down.
Query 3 of 10
"How has the median flat price in Lewisham changed over the last 5 years?"
Compare a cheaper borough. If Lewisham's prices are also stable, it confirms the entry-level market hasn't run away across the board.
✓ Real data — HM Land Registry 2021–2025
Median Flat Price — Lewisham
2021
£361,750
2022
£370,000
2023
£370,000
2024
£365,000
2025
£368,000 (+1.7%)
Lewisham moved just +1.7% over five years. No bubble, no crash. For a first buyer, this is the signal that matters: you haven't been priced out while saving. The entry point is lower than Tower Hamlets and the market is highly stable.
Step 4 — How Active Is the Market?
Query 4 of 10
"How many flats sold in Tower Hamlets in 2025?"
A thin market means fewer choices and slower searches. You want a borough with enough volume to be selective, not one where you compete for 3 listings.
✓ Real data — HM Land Registry 2025
2,370 flat transactions in Tower Hamlets in 2025 — one of London's most liquid flat markets. Roughly 200 sales per month. Plenty of opportunities to be selective.
Step 5 — How Much of the Market Is Within Budget?
Query 5 of 10
"What percentage of flats in Tower Hamlets sold for under £500,000 in 2025?"
Confirms whether your budget is realistic in the real market. If only 10% of flats sold under your number, you'll be competing hard for scarce stock.
✓ Real data — HM Land Registry 2025
59.1% of Tower Hamlets flats sold for under £500,000 in 2025 (1,401 of 2,370 transactions). A broad, accessible market at entry-buyer budgets. Most of the borough's flat transactions happen below that threshold.
Step 6 — Avoid the New Build Trap
Query 6 of 10
"What is the new build vs resale flat price in Tower Hamlets?"
New build marketing targets people who've been renting and are excited about a fresh start. The premium is almost always enormous — and you often lose it the day you move in.
✓ Real data — HM Land Registry 2025
New Build vs Resale — Tower Hamlets Flats 2025
Resale flat
£440,000
New build flat
£709,350
£269,350 new build premium. That's more than a year's gross salary for most London workers — paid at the front door of a property that often falls back toward resale values within 2–3 years. Buy resale.
Step 7 — Drill Into Postcodes
Query 7 of 10
"Which postcode in Tower Hamlets had the lowest median flat price in 2025?"
Borough averages hide massive variation. Two postcodes in the same borough can differ by £100,000+.
✓ Real data — HM Land Registry 2025
Median Flat Price by Postcode — Tower Hamlets 2025
E3
£420,000
E1
£440,000
E14
£460,000
E2
£500,000
E1W
£730,000
E3 (Bow / Mile End) has the lowest postcode median in Tower Hamlets at £420,000 — 500 transactions in 2025, with good supply. It sits on the District and Hammersmith & City lines. Note: the borough's lower quartile (£365,000) reflects the cheapest 25% of sales across all postcodes — not any single postcode's median.
Query 8 of 10
"How has the flat price in E3 changed since 2020?"
Is the cheapest postcode cheap for a reason, or just less discovered? A stable or slightly rising trend is a green flag. A sharp decline warrants investigation.
Step 8 — Check the Cheaper Alternative
Query 9 of 10
"What is the lower quartile flat price in Lewisham?"
Always compare at least two boroughs. A £78,125 gap between Tower Hamlets (£365,000) and Lewisham (£286,875) can mean the difference between a 5% and 10% deposit being reachable.
✓ Real data — HM Land Registry, current to Feb 2026
Lewisham lower quartile: £286,875 — a meaningful step down from Tower Hamlets. If the commute from SE-London works, the calculator above will show a very different deposit timeline at that price point.
Step 9 — Get the Latest Signal
Query 10 of 10
"What is the early 2026 flat price in Tower Hamlets?"
The most recent Land Registry data. If prices started moving up in January–February 2026, the window is narrowing. If flat, you're not under immediate pressure.
→ Tower Hamlets lower quartile: £365,000. At 10% deposit (£36,500), saving £600/month at 4.5% ISA rate takes about 57 months (4 yr 9 mo) — during which roughly £120,000 in rent is paid.
→ Loan: £328,500. Monthly mortgage at 4.5% over 25 years: ~£1,820/mo — £280/mo less than current rent of £2,100. Buying is cheaper month-to-month once you get there.
→ Income check: £65,000 × 4.5 = £292,500 max mortgage. Loan needed: £328,500 — a shortfall of ~£36,000. Options: add a co-buyer, target Lewisham at £286,875 instead (loan ≈ £258k, well within range), or save for 15% deposit to bring the loan down.
→ Tower Hamlets flat prices fell 15.6% from their 2021 peak (£539,000 → £455,000 median). The lower quartile also fell, from £407,545 in 2021 to £365,000 in 2025 — the deposit target got easier while this buyer was saving.
→ E3 (Bow/Mile End) has the borough's lowest postcode median at £420,000 (500 transactions). The borough-wide lower quartile of £365,000 reflects the cheapest 25% of sales across all postcodes — achievable in E3 for well-priced resale flats.
Logical next step: Run the calculator with the Lewisham lower quartile (£286,875) as the property price. The numbers change significantly. Then speak to a mortgage broker to get a real AIP (Agreement in Principle) — that's what turns the data into a buying decision.
⚠️ This is a demo only. All Land Registry figures are from HM Land Registry public data. The calculator is illustrative — it uses simplified assumptions (25-year term, income × 4.5 rule, no SDLT/legal fees included). Actual mortgage affordability depends on your full financial profile. This guide does not constitute financial, mortgage, or property investment advice. Always consult a qualified advisor before making a purchase decision.