What I Check Before Buying a Unit: Building Defects, Strata Problems, and NBN

I saw a question in a landlord group the other day from someone thinking about buying a unit in an older building. They'd heard a few whispers: possible building defects, strata fees on the rise, and NBN speeds that were all over the place. It reminded me of my own early days managing units, and how much I wish someone had sat me down with a simple checklist.

When you buy into a strata scheme (that's the Australian term for what other places call an owners corporation or condo association), you're not just buying the four walls of your unit. You're buying a share of the entire building — the roof, the balconies, the common plumbing, the basement, the lot. And that means the building's problems become your problems, often with a bill attached.

Here's what I'd dig into before signing anything, based on what I've seen go wrong.

Start with the Strata Records

Before you even think about making an offer, get your hands on the full strata report. This is a bundle of documents that includes the AGM minutes, financial statements, the sinking fund forecast, and any correspondence about major works. I'm not a lawyer and this isn't legal advice, but I always recommend having a conveyancer or solicitor go through this with you — they'll spot things you might miss.

Look for two big red flags: special levies and ongoing repair discussions. A special levy is an extra one-off charge on top of the regular quarterly fees, usually raised to cover a big unexpected repair. If the minutes keep talking about "roof membrane replacement" or "balcony waterproofing," that's a sign the building has a known defect that hasn't been fixed yet. And if they've already raised one special levy, ask yourself: is there a track record of more to come?

In the question I read, the unit looked beautiful, but the strata fees were nearly three thousand a quarter. That's high. The reason? The building was halfway through roof and balcony membrane repairs, and the levy was still dragging on. A new owner walking in would be inheriting that cost.

Look for Water: Roofs and Balconies

Water is the enemy of any building, but especially multi-storey units. The roof membrane is the waterproof layer that stops rain from seeping into the structure. Balconies have their own membranes too, usually under the tiles. When a membrane fails, water gets into the concrete, rusts the steel reinforcement, and causes spalling — that's when chunks of concrete start flaking off. It's not just ugly; it's a structural issue.

So when you inspect a unit, don't just look at the paint and the floorboards. Go outside onto the balcony, if there is one. Check for cracks, lifting tiles, or staining on the ceiling below. Ask the strata manager directly: "Has the building had any waterproofing issues, and have they been fully rectified?"

And while you're at it, check the drainage. The question mentioned the building was rated low flood risk overall, but storm-water flow near a cul-de-sac could affect the lower levels over time. That's the kind of detail you'll never find on a real estate listing — you need to walk the site after heavy rain or ask long-term residents.

Test the NBN Before You Commit

This one gets overlooked all the time. If you're buying a unit to live in or rent out, internet speed matters. Many older buildings have NBN FTTB — Fibre to the Basement. That means the fibre comes into the building's basement, but the last stretch to each apartment runs over the old copper phone lines. And here's the thing: copper degrades. In the building I read about, one apartment got 110 Mbps and another got 25 with constant dropouts. Same building, same FTTB, wildly different results. The difference? The quality of that internal copper wiring.

Here's the kicker: fixing that internal copper isn't something you can do on your own. It usually requires the owners corporation to approve and coordinate upgrades through the building's telecommunications infrastructure. If the strata committee isn't interested, you could be stuck with slow internet for years.

So before you buy, knock on a few doors or talk to the building manager. Ask current residents what speeds they actually get, not what the provider advertises. Run a speed test on your phone in the unit if you can. And ask if there's been any talk of upgrading to fibre-to-the-unit or installing a new internal network.

My Non-Negotiable Checklist

After managing units for years, here's what I'd do before buying any strata unit:

1. Read every page of the last two years of strata minutes.
2. Check the sinking fund forecast — is it adequately funded for the building's age?
3. Ask if any special levies have been raised in the past five years, and for what.
4. Inspect the roof space, the basement, and every balcony you can access.
5. Run a water test on any external area: pour a little water and see if it drains away or pools.
6. Test the NBN yourself with a speed test app, and ask neighbours about their experience.
7. Talk to the building manager or caretaker if there is one — they know where the bodies are buried.

Buying a unit is exciting, but the wrong building can turn into a money pit. Do the due diligence now, and you'll thank yourself later. And if you're already a landlord, what's the worst strata surprise you've ever found? I'd love to hear your stories — it might save someone else from the same mistake.