GetPost Labs is a technology company. We work with property data: the data you supply (loans, rent, costs, documents) and the data we research (sales, rents, rates and rules), and we apply our experience in building data and software systems to lay it out clearly. The outcome is structured information to help you answer your own questions with data. It is not financial, tax, legal, credit or valuation advice, and it is not a recommendation to buy, hold or sell.
The property, address and owners in this example are fictional, and the figures are rounded 2026 assumptions. Real outcomes depend on your circumstances and the market, so check decisions with a licensed financial adviser, accountant or registered valuer.
The story
A family of four has outgrown their three-bedroom home and wants a four-bedroom house near a better school. They own 12 Paperbark Street, south-east QLD fictional, a 3 bed, 1 bath house they have lived in for eight years. It is worth about $850,000 and they owe $420,000. They have $60,000 in savings.
They have found 5 Satinwood Court, south-east QLD fictional, a 4 bed, 2 bath family home listed at $1,250,000. Their questions: what will the whole move cost, how big will the new loan be, what will repayments be, and should they sell first, buy first, or keep the old home as a rental?
Including $45,225 stamp duty
After selling costs and the loan
67.2% of the new home’s price
A month, up from $2,572
1. Selling the current home
| Sale price (estimate) | $850,000 |
| Less agent commission (about 2.2% including GST) | −$18,700 |
| Less marketing, photos and online listings | −$4,000 |
| Less conveyancing (sale) | −$1,200 |
| Less loan discharge fee | −$350 |
| Less the home loan paid out | −$420,000 |
| Equity released at settlement | $405,750 |
The home was bought for $560,000 and has been the family’s main residence the whole time, so the $290,000 gain is exempt under the main residence exemption.
2. Buying the new home
| Purchase price | $1,250,000 |
| Stamp duty (Queensland home concession rate, as they will live in it) | $45,225 |
| Transfer registration (Titles Queensland, approximate) | $5,200 |
| Mortgage registration | $240 |
| Conveyancing (purchase) | $1,600 |
| Building and pest inspection | $650 |
| Loan application and valuation | $600 |
| Removalists | $2,500 |
| Total cost of the purchase | $1,306,015 |
Stamp duty uses the Queensland Revenue Office home concession rates. It would be higher at the general rate if they did not move in. First home concessions do not apply because they already own a home.
3. Where the money comes from
| Total cost of the purchase | $1,306,015 |
| Less equity from the sale | −$405,750 |
| Less savings | −$60,000 |
| New home loan | $840,265 |
| Loan-to-value ratio | 67.2% |
| Repayments at 6.2% over 30 years | $5,146 a month |
| Change from today | +$2,574 a month |
At 67.2% of the price, the loan is under 80%, so there is no lenders mortgage insurance. The bank will still check that the family’s income can carry $5,146 a month with a buffer of about 3% on the rate.
4. Three ways to do it
| Option | Extra cost | Borrowed | Monthly | Main risk |
|---|---|---|---|---|
| A. Sell first, then buyShort rental and a second move | $9,300 | $840,265 | $5,146 | Buying market moves while you wait; you may need to rent between settlements |
| B. Buy first with a bridging loanBridging interest for 4 months and fees | $10,197 | $840,265 | $5,146 | If the old home sells 5% lower, about $42,500 less to put in |
| C. Keep the old home as a rentalNo sale costs | — | $1,666,015 | $7,920 | Much higher debt; the new home’s loan interest is not tax-deductible |
A. Sell first, then buy
The safest on money: they know exactly how much equity they have before they commit. The catch is timing. If the new home is not settled when the old one is, they rent for a few weeks and move twice, about $9,300 here. They can also ask the buyer for a longer settlement.
B. Buy first with a bridging loan
Useful when the right house comes up first. The bank lends against both homes until the old one sells, charging interest on the bridging amount, here about $9,197 over 4 months at 6.8% plus fees. The real risk is the sale: if the old home sells for 5% less than expected, they have about $42,500 less to reduce the loan.
C. Keep the old home as a rental
They keep the old home, rent it for about $700 a week, and borrow the whole purchase. Total debt becomes $1,666,015 across both properties, and they pay about $7,920 a month net of rent, compared with $5,146 if they sell.
- The rental only just covers its own interest and costs (about $1,360 a year before tax), so there is little tax benefit
- The $1,246,015 borrowed for the new home is for a private purpose, so its interest is not deductible, even though the old home is rented
- When the old home is first rented, its cost base for capital gains tax resets to its market value then; only later growth is taxed when it is sold
- Lenders look at total debt against both homes: $1,666,015 against $2,100,000 is about 79.3%
5. The timeline
| When | Step | What happens |
|---|---|---|
| Weeks 1–2 | Get ready | Loan pre-approval for the new home; two or three agent appraisals on the current home; decide sell first or buy first |
| Weeks 3–4 | List the current home | Photos, styling and repairs; listing goes live; building and pest reports if you want to offer them to buyers |
| Weeks 4–8 | Sell | Open homes and offers; contract signed; buyer’s finance and building and pest conditions, usually 14–21 days |
| Weeks 5–9 | Buy | Inspect and make an offer; contract signed; 5 business days cooling-off in Queensland; your own finance and building and pest conditions |
| Weeks 9–12 | Settle the sale | Buyer settles, your loan is paid out and the discharge is registered; the equity is released |
| Weeks 10–13 | Settle the purchase | New loan drawn, stamp duty paid, transfer registered; keys collected |
| Weeks 12–14 | Move | Removalists, utilities and address changes; final meter readings at the old home |
A typical sell-first timeline. Settlement periods are usually 30–45 days and can be negotiated so both settlements fall on the same day.
6. The whole move in one view
| Costs of selling | $24,250 |
| Stamp duty | $45,225 |
| Other costs of buying and moving | $10,790 |
| Total cost of changing homes | $80,265 |
| As a share of the new home’s price | 6.4% |
Changing homes costs about $80,265 before any renovations, most of it stamp duty and the agent. Selling first gives a loan of $840,265 and repayments of $5,146 a month. Keeping the old home as a rental is possible, but it more than doubles their debt, and the extra interest on the new home is not deductible.
Method and sources
Repayments are principal and interest over 30 years. Stamp duty uses the Queensland Revenue Office home concession rates; the transfer registration fee is an approximation of Titles Queensland fees, which rise with the price. Agent commission and other costs are typical ranges, not quotes. Tax points are general: main residence exemption, the purpose test for interest deductions, and the market value cost base rule when a home is first rented.
Everything on this page is for educational and informational purposes only. Costs, prices, interest rates, rules and government schemes change over time, and the figures shown are approximate examples that may already be out of date. Nothing here is financial, tax, legal, building or professional advice, a recommendation or a quote. Do your own research, get written quotes and seek advice from qualified professionals before making any decision.
PropertyMaths is being built by GetPost Labs Pty Ltd, a technology company. We are not financial, tax, legal or property advisers. The information here is our own research, shared to show what a product for property owners and investors could do.