Selling A Bishan 4-Room At S$789,000 To Buy In District 20 — The Three Sets Of Numbers At 2Q2026's Medians

This is an illustrative example on the quarter's median prices and a stated household, not a real family and not advice on whether to sell, buy, keep or rent out. It lays out the figures the position engine computes for each side of the question; the decision is the reader's.

Three separate questions sit inside one move. What does the flat actually net once the loan and the selling costs come out? What does the condo cost on day one, and every month after? And what happens if nothing is sold at all? We ran all three through the position engine at the same quarter's medians, so the sides can be read next to each other.

According to data.gov.sg HDB resale records, the median 4-room resale price in Bishan in 2Q2026 was S$789,000, across 54 sales. Six years earlier, in 2Q2020, the median was S$552,500 across 28 sales. On the private side, URA Data Service caveats put the median for a 60 to 99 sqm unit in District 20 at S$1,743,000 in 2Q2026, across 32 sales, at a median 904 sqft. Both are indicative medians from recorded transactions, not valuations of any one home. The household in this example is illustrative: a 75% HDB loan taken in 2Q2020, six years of payments behind it.

The flat's median has moved 42.8% since the purchase quarter, but the loan balance decides what the sale actually nets

Start with the sale. The median has moved S$236,500 between the two quarters, or 42.8%. That is the headline figure, and it is also the one that flatters the position most. It is a move in medians, not a tracked resale of the same flat. Mix matters here: 28 sales set the 2Q2020 median and 54 set the 2Q2026 one, and block, floor and lease differ across them.

Against that sits the debt. The original 75% HDB loan was S$414,375, and the balance after six years is about S$337,941. Selling costs for agent and legal work come to about S$20,470. Seller's stamp duty is S$0 at this holding period. What is left is about S$430,589 in net proceeds. That is the number the next two sides of the question have to work with.

The table below sets out the flat side in full.

The condo needs S$492,500 before the loan, and the sale proceeds do not cover it

Now the purchase. At the 2Q2026 median of S$1,743,000, buyer's stamp duty is S$56,750. The maximum loan is S$1,307,250, set at 75% by the loan-to-value limit rather than by income. That leaves S$87,150 in minimum cash and S$348,600 in CPF or cash. Added to the stamp duty, the engine puts S$492,500 as the amount needed before the loan starts.

Set that against the net proceeds from the flat and the gap is S$61,911, shown in the table as a negative figure. It has to come from somewhere other than the sale. The engine does not assume where.

Sequence changes the arithmetic sharply. Bought after the flat is sold, ABSD is S$0. Bought before, ABSD applies at 20%, or S$348,600, under the rules as recorded. Remissions are not modelled here, so the second row is the gross position.

The monthly instalment moves from about S$1,880 to S$5,892, and the test rate moves it again

The monthly side is the part a household feels. The flat's instalment runs at about S$1,880. The condo's instalment, on a loan of S$1,307,250 at 3% over 27 years, is about S$5,892. The difference is S$4,012 a month.

The second row of the table below is a test rate, not a projection of where rates go. At 4%, the condo instalment is S$6,604, and the flat's is S$2,118. The engine shows both so the monthly figure is not read off a single rate assumption.

One thing the table cannot show is how long the tenure holds. The 27-year term follows from the stated age of 38. A shorter term would lift the monthly figure; the medians would not change.

Five years of holding the condo costs S$312,714 in the engine's run, S$183,896 of it interest

Monthly instalments are only part of the cost of holding. The engine totals five years of ownership at S$312,714, of which S$183,896 is interest. On those assumptions, the price would need to rise 18.3% over the five years for the position to come out level.

That 18.3% is a break-even calculation, not a statement about where District 20 prices go. It rests on stated inputs: a sale at today's indicative mid value after five years, 2% commission plus S$3,000 in legal fees with 9% GST, and interest from a standard amortisation schedule at the given rate. Change the rate or the exit costs and the break-even figure changes with them.

It is worth saying plainly what this row is measuring. It is the cost of carrying the asset, not a view on the asset.

Keeping the flat and renting it out produces a net carry of S$29,164 a year

The third side moves nothing. Rental approvals recorded on data.gov.sg give an estimated S$3,700 a month for the flat, drawn from 55 approvals in the period. Against the 2Q2026 median that is a gross yield of 5.6%.

From there the engine works down. Property tax at the non-owner-occupied rate is S$1,865 a year, on an assumed annual value of S$45,900. Maintenance is S$900 a year. After vacancy, tax and maintenance, net rent is S$37,950 a year. Interest on the remaining loan takes S$8,786. The net carry is S$29,164 a year, or 3.7%.

Two caveats sit under those figures. The rent is an estimate from 55 approvals, which is a modest sample, and approvals do not always reflect what a specific unit achieves. The net carry also assumes the existing loan keeps running at its current rate. The table below shows each line.

What the figures do not settle is the part that sits outside the medians. Both medians rest on small counts, 54 resale sales and 32 private sales in the quarter. Mix can move either one between quarters. The rates used for stamp duty, ABSD and LTV are versioned data in the engine's rules file, checked against IRAS and MAS publications on 2026-09-18, with the applied version effective from 2025-07-04. They change from time to time, and the arithmetic changes with them. Next quarter's data will show whether the Bishan 4-room median and the District 20 median for 60 to 99 sqm units hold at these levels, and whether rental approvals stay near S$3,700.

A single median rarely answers a question like this one. It is one figure, from one quarter, from a handful of recorded deals. What it is good for is placing a position: the gap between what the flat nets and what the condo asks, the monthly figure at two rates, the yearly carry if neither happens. Read together, those three sides describe a decision; read alone, any one of them describes very little. The direction across quarters is where the figures start to mean something.

Method: the flat is a 4-room in the town, bought at the median of Q2 2020 with a 75% HDB loan at 2.6% over 25 years, of which 6 years have been paid. Its value today is Q2 2026's median. Selling costs, seller's stamp duty, equity, the rent estimate and the carry are the position engine's under the rules recorded as in force. The condo is a 60 to 99 sqm resale in the nearest district with enough sales within 2.5 km of the town. It is taken at Q2 2026's median. The buyer is a citizen aged 38 with a household income of S$15,000 a month and no other debt. sale at today's indicative mid value after 5 years. Seller pays 2% commission and S$3,000 legal fees, plus 9% GST. Mortgage interest from a standard amortisation schedule at the given rate. Loan of S$1,307,250 (75% of the price), the maximum available. Property tax on an assumed annual value of S$45,900 (85% of market rent). Maintenance at the configured norm. Rates are versioned data in config/rules.yaml, checked against IRAS and MAS publications on 2026-09-18. The newest version applied here took effect 2025-07-04. Rules change with each cooling-measure round. Private figures are from URA Data Service caveats, HDB figures from data.gov.sg resale records, both loaded weekly by this site's ingest. Medians are of the non-excluded transactions in the period named. Sales flagged by the hygiene rules (related-party transfers, bulk deals, outliers) are left out. Every figure is indicative and drawn from recorded transactions, not a formal valuation.