Property investment, weighed up.

It can be, and it's been kind to a lot of New Zealanders, but “property always goes up” is a story, not a guarantee. Returns come from rent and from any rise in value, minus a long list of costs, and the last decade's gains are no promise of the next.

Whether it suits you depends on your finances, your appetite for debt and hassle, and your timeframe. Since we don't advise on investments, nothing here is a recommendation — just the groundwork for a clear-eyed decision.

Yield is the rent as a percentage of the property's value. Gross yield is annual rent divided by the price; net yield subtracts the running costs — rates, insurance, maintenance, management and vacancy — which gives a far more honest picture.

Many New Zealand rentals have low net yields, meaning the rent doesn't cover all the costs plus the mortgage, and investors rely on future value growth to come out ahead. That's a bet, not a certainty, so the numbers matter.

Leverage is property's real difference from most investments: you can borrow a large share of the price, so you control a big asset with a smaller amount of your own money. If the property rises, your return on that deposit is amplified.

The catch is that leverage cuts both ways — it magnifies losses just as much, and you owe the debt regardless of what the property does. It's the source of both the appeal and the risk.

The bright-line test can tax the gain when you sell a residential property within a set period of buying it — a limited form of capital gains tax on property. The main home is generally excluded.

The length of that period has been changed several times by different governments, so any specific number dates quickly. Check the current rule on ird.govt.nz, and take advice from an accountant before buying or selling.

The rules on deducting interest on residential rental property have changed repeatedly in recent years — phased out, then reinstated — which has a big effect on whether a rental runs at a profit or a loss for tax.

Because this has moved so much, don't rely on older advice. Confirm the current position with an accountant and on the IRD website before you model any numbers.

Beyond the mortgage, budget for rates, insurance, maintenance, and periods with no tenant. There's also compliance — healthy homes standards, tenancy law and the paperwork — plus the time and stress of dealing with tenants and repairs.

A property manager handles much of this for a fee, which eats into yield but buys back your time. “Passive income” is generous wording for rental property; it's more like a part-time job with occasional 2am phone calls.

Deposit requirements for investment properties are usually higher than for your own home, and they move with Reserve Bank lending rules. Lenders also assess the rent and your other income to decide what you can borrow.

Because these settings change, check the current requirements rather than assume. A mortgage adviser can tell you what's realistic for an investment purchase in the current environment.

They behave differently and suit different people. Property lets you leverage and feels tangible, but ties up a lot in one asset, costs a lot to buy and sell, and comes with hands-on hassle. Shares and funds are easy to diversify, cheap to trade and quick to sell, but you watch the value bounce around daily.

There's no universal winner. Our investing page digs into the shares side; the honest answer usually depends on your situation, not a rule.

The big ones: interest rates rising and squeezing a tightly geared property, long vacancies, expensive maintenance surprises, and the difficulty of selling quickly if you need the cash. It's a concentrated, illiquid bet, often in a single town.

There's also the risk of overcommitting — stretching to buy a rental can leave you exposed if your own income stops. Making sure your own foundations are solid first is rarely the exciting option and usually the right one.

Paying down your own mortgage is a guaranteed, tax-free return equal to your interest rate, with no tenant, no maintenance and no risk. Buying a rental is a leveraged bet on rent and future value, with real costs and hassle attached.

Neither is universally right, but clearing high-interest debt and building a buffer usually comes first. Beyond that it's a personal call best made with the actual numbers — and, for the tax side, an accountant.