Not every defect is a reason to walk. The ones that matter are the ones that affect insurance, financing, or the pool of people who can buy it from you later.
Buyers tend to treat every inspection finding as equivalent. They are not. It helps to sort anything found into three groups.
The third group is small. Most of what an inspector finds is tier one or two.
Poly-B plumbing and aluminum wiring are both common in specific build eras here, both are still in thousands of Calgary homes, and both can affect what an insurer will write and at what price. Neither is automatically a deal breaker. Both are things you want to know before you remove conditions, not after.
Basement moisture in Calgary is usually a grading, downspout or window-well problem rather than a foundation failure — which is good news, because those are fixable for a few thousand dollars. But you have to establish which it is. Efflorescence on foundation walls, a dehumidifier running in a finished basement, and fresh paint on the bottom of a wall are all worth asking about directly.
Hairline vertical cracks in a poured foundation are extremely common and rarely significant. Horizontal cracks, stepped cracking in block, doors that will not latch, and floors out of level are a different conversation and warrant an engineer, not just an inspector.
Calgary sees more damaging hail than almost anywhere else in the country, and that shortens asphalt shingle life meaningfully. A roof that would last 20 years elsewhere may not here. Ask the age, ask whether it has been through a claim, and ask whether the claim was paid out and the work actually done.
A basement development, a suite, a wall removed, a deck. Unpermitted work is a discount rather than a feature, can complicate insurance, and becomes your problem to disclose when you sell. Permits are searchable — ask for them.
The useful question is never "is this bad?" It is "what does this cost, who else will care, and does it change what the house is worth?" A $12,000 roof on a home priced as though the roof were new is a negotiation. The same roof on a home already priced for it is not.
The most expensive mistake is not buying a house with problems — almost every house has problems. It is buying one without knowing which problems, and paying the price of a house that does not have them.