How to set a buying budget you'll actually stick to
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Borrowing capacity vs purchase price

What's the difference between your borrowing capacity and your maximum purchase price?

Your borrowing capacity is what a lender will lend you; your maximum purchase price is what you can actually afford once deposit, costs and a safety buffer are accounted for. They're rarely the same number — and borrowing to your limit is how buyers get stretched.

In our experience, this is the single most expensive misunderstanding we see before exchange: a buyer treats the bank's "you can borrow X" as their shopping budget. It isn't. The bank's number is the most you could repay today; your number is what still works after stamp duty, the other costs, and a bad month or two.

Borrowing capacity vs max purchase price (they're not the same)

Borrowing capacity is what the lender will give you, based on income, debts, expenses, dependents, and the assessed rate. The bank's ceiling.

Max purchase price is what you're willing to pay. It sits below the bank's ceiling, accounting for stamp duty, conveyancing, building and pest, LMI, moving costs, and a buffer for rate rises or life going sideways.

The bank's "you can borrow $750,000" means you'd survive repayments today — not with two kids, a rate rise, and a hot water system replacement at the wrong moment.

Visual: Borrowing capacity vs max purchase price

What the bank will lend
$750,000 (bank's ceiling)
What you should spend
$680,000 (your ceiling)
ComponentAmountWhy it matters
Max purchase price$680,000The number you actually offer
Stamp duty + costs~$30,000Conveyancing, B&P, rates adjustments, moving
Safety buffer~$40,000Rates rising, life going sideways, hot water replacement
Bank's ceiling$750,000What they'll lend, not what you should spend
A lender saying you can borrow $750K doesn't mean you should buy a $930K house. Your number sits below the bank's number and accounts for the costs they don't show you.

Common questions

Is your borrowing capacity the same as your maximum purchase price?

No. Borrowing capacity is the most a lender will lend you; your maximum purchase price sits below that once you account for stamp duty, conveyancing, inspections, LMI and a safety buffer. Treating the bank's ceiling as your shopping budget is how buyers get stretched.

Why is my real budget lower than what the bank approved?

Because the bank's figure is what you could repay today, not what leaves you comfortable. It doesn't set aside the upfront costs (stamp duty is the big one) or a buffer for rate rises, a quiet month, or an unexpected repair. Your real ceiling builds those in, so it comes in under the approval.

Should I borrow to my full capacity?

Usually not. Borrowing to the limit leaves nothing for a rate rise or a change in circumstances, and it's the most common way a comfortable purchase turns stressful. Leaving headroom below your capacity is a deliberate safety margin, not money left on the table.

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