When to Sell Your Investment Property: The One Rule I Actually Follow

A client messaged me last month. "Yan, my property's gone up $300K. Should I sell?" Same week, another client: "I bought at the wrong time, I'm underwater, should I cut my losses?"

Both wrong. Both asking the wrong question entirely.

I've held property across three states over the past decade. I've sold twice. And both times, I made the decision the same way — not based on whether I was up or down, but based on something far more boring and far more reliable. Whether the reasons I bought the thing still existed.

That's it. That's the whole framework. But the application of it — that's where most investors fall apart, because most investors can't actually articulate why they bought their property in the first place.

The problem with profit-based selling decisions

Here's what I see constantly. An investor buys a property in, say, Cranbourne for $610K. Two years later, comparable sales suggest it's worth $750K. They feel clever. They start running numbers on what they could do with $140K in equity. Should they sell? Should they refinance? Should they—

Stop. The fact that it went up tells you nothing about whether it will continue to go up. And the fact that another property went down tells you nothing about whether it's a bad hold.

I'll give you a real example from our portfolio. We helped a client purchase in Hampton Park at $590K — a property that was frankly in shocking condition. White ant damage, leaking roof, foundation cracks 1. Our reno team went in, did structural repairs, and we got it rented at $850 per week. CBA valued it at $670K without even sending an inspector on-site.

Now. If that client had sold at $670K, they would have "made" $80K. But why would they? The original buying thesis was: large land (600+ sqm), strong rental demand from Indian and Sri Lankan families, land value comprising over 80% of purchase price, positive cash flow after renovation. Every single one of those conditions still holds today. Affordability ratio in Hampton Park is still under 7x median household income 2. Population growth hasn't slowed. There's no new land supply coming.

So why on earth would you sell?

My actual system: the checklist in the safe

I'm an actuary by training. I don't trust gut feelings. I trust systems.

When I buy a property, I have roughly 30 criteria I evaluate. Not all carry equal weight, but they all get documented. Things like:

• Affordability ratio (median house price to median household income) — must be under 7x
• Land value as a percentage of purchase price — must exceed 80%
• Owner-occupier ratio in the suburb — must exceed 60%
• Vacancy rate — must be under 3%
• Days on market trend — declining or stable, not rising
• Population-to-dwelling ratio — above 2.5
• Unit stock percentage — below 20% to avoid apartment drag on house prices
• Rental yield post-renovation — above 5%

Every single criterion gets written down. Literally on paper. I put it in my safe. My safe doesn't hold cash — it holds these checklists 3. That might sound eccentric, but it's the most valuable thing I own, because those checklists are my memory of why I made each decision.

Every six months, I pull them out. I go through each criterion again with current data. CoreLogic for price movements. SQM Research for vacancy rates and days on market. ABS census data for population shifts 4. I re-tick or re-cross each item.

If I started with 30 ticks and now I've got 10 crosses — I'm on alert. When 15 of the 30 have flipped to crosses, I sell. No emotion. No "but I love this house." No "but the market might bounce back." Fifteen crosses means the investment thesis is broken. Get out.

When the thesis breaks because you were right

Most of the time, a thesis breaks for a good reason: the property has done its job.

Think about it. You bought because affordability was excellent — price-to-income under 7x. The property doubled in value over eight years. Now affordability is 11x. Well, congratulations. You made money. But the conditions that made it a good buy no longer exist. The next wave of buyers faces stretched affordability, higher mortgage repayments relative to income, and a shrinking pool of qualified purchasers.

That's when I sell. Not because I'm panicking. Because the maths changed.

Li Ka-shing — the Hong Kong property billionaire — started liquidating mainland China assets in 2016 5. People called him senile. Property prices kept rising for another five years after he sold. By 2024, many of those markets had retreated to 2016 levels. He didn't try to time the peak. He just recognised that the conditions which made those assets attractive had deteriorated past his threshold.

I'm no Li Ka-shing. But I respect the principle: never try to squeeze out the last dollar. Sell when your reasons expire, not when the price peaks.

When the thesis breaks because you were wrong

This one hurts more but it's equally important.

I've had clients who bought based on a rumour. "My mate said they're building a massive shopping centre nearby." Five years on, no shopping centre. No development application. No rezoning. Nothing.

That's a thesis failure too. The buying reason — anticipated infrastructure driving capital growth — turned out to be fiction. The property might not have lost money in nominal terms, but it's underperformed. It's been sitting there, consuming holding costs, while better-located assets in the southeast corridor appreciated 12-16% in a single year 6.

In that case, even if you're technically "losing money" on the sale (after stamp duty, agent fees, and CGT), you should still consider selling. Because every year you hold a dud property is a year your capital isn't deployed somewhere productive.

Opportunity cost is the silent wealth destroyer. Your money sitting in a flat-lining asset in the wrong suburb could have been in Cranbourne or Narre Warren or Hampton Park, pulling $850 a week in rent on a $590K purchase 7. That's real dollars you're forgoing.

I had one portfolio where I sold a Sydney property at a modest loss and redeployed the capital into two Melbourne southeast houses. Within 18 months, those two properties had appreciated more than the Sydney property had in the previous four years. Losses on paper stung for about a week. The portfolio performance spoke for itself.

The affordability ceiling — my hard exit trigger

Of all my criteria, affordability ratio is the one I weight most heavily. And I have a hard rule around it.

When median house price exceeds 10x median household income in a suburb, I start considering an exit. When it exceeds 14x, I don't consider — I execute 8.

Why 14x? Because historically, no Australian housing market has sustained a price-to-income ratio above 14x for more than a few years without either a correction or a prolonged period of stagnation. Sydney hit 14x in 2017. Prices fell 15% over the next two years. Parts of Perth exceeded 10x in 2014 on the back of the mining boom. They flatlined for seven years 9.

Melbourne's median sits around 7-8x right now — which is precisely why I'm all in on Melbourne and have been for the past three years 2. Every dollar I have is deployed here. When people ask me "isn't that risky, putting everything in one market?" I say: show me another capital city where you can buy 600sqm of land with a house for $600K-$700K, get it rented at $800+ per week, and the price-to-income ratio is still under 8x. I'll wait.

Australian housing isn't one market. It's eight capital cities and dozens of regional markets, all running on different cycles. Right now, Melbourne's cycle position is where Sydney was in 2019 and Brisbane was in 2020 — the bottom. History doesn't repeat, but the rhythm of affordability-driven cycles is about as close to a pattern as property markets get 10.

What this means for renovation and development decisions

There's a direct link between exit strategy and renovation strategy that most investors miss.

If your thesis says "hold for 10+ years, maximise rental yield," then your reno strategy should focus on income-generating improvements. Granny flat additions ($110K build cost, 18% gross ROI in the right suburbs), room reconfigurations to boost per-room rental income, cosmetic upgrades that justify above-market rent 11.

But if your thesis is showing cracks — affordability deteriorating, vacancy rates creeping up, new supply entering the market — then spending $60K on a granny flat is the wrong move. You're adding capital to a declining thesis. That $60K is better deployed as a deposit on your next property in a market where the thesis is still strong.

We had a client last year with a property in a western Melbourne suburb. The numbers were marginal — rental yield around 3.5%, land value ratio around 65%, affordability pushing 9x. He wanted to build a granny flat to boost cash flow. I talked him out of it. "The problem isn't your cash flow," I told him. "The problem is your thesis. This suburb has too much new land supply from greenfield estates. Your property isn't going to appreciate meaningfully regardless of what you build on it. Sell. Redeploy."

He sold. Bought two properties in the outer southeast. Both are now returning 6%+ yields with renovation, and both sit in suburbs where land supply is genuinely constrained 7. That's what a functioning exit strategy looks like — it informs every subsequent decision.

Be cold-blooded about it

I'll leave you with this. The best investors I've met — and I include a few of our clients who've built portfolios of six or seven properties — share one trait. They are spectacularly unsentimental about property.

They don't fall in love with a house. They don't hold onto a property because "we've had it so long" or "the tenant is lovely" or "it might come back." They track their thesis, review it regularly, and act when the data tells them to act.

Profit or loss is irrelevant to the sell decision. The only question that matters: do the reasons I bought this property still hold?

If yes, hold.

If no, sell.

The more cold-blooded you are, the more rational you are, the more money you make over a 20-year investment horizon. Emotions are for choosing where you live. Data is for choosing what you own.

I'm Yan Zhu. I keep checklists in my safe and I sleep just fine.