These are the ones we see go wrong, in both directions.
The four-year lookback counts your spouse. A buyer who has never owned property can fail the first-time buyer test because their spouse owned a condo four years ago — before the two of them met. When the relationship started doesn’t enter into it.
It runs on calendar years, not rolling months. Closing in December rather than January can change the answer, because the lookback measures whole calendar years.
Primary residence means primary residence. A property bought as an investment, or a second home, doesn’t qualify for the homeowner rebates. It may qualify for the rental rebate instead — a different program with different rules.
You must be the first to occupy. If someone lived in it before you, including a tenant, the homeowner rebate generally isn’t available.
Owning isn’t the same as living in. The first-time buyer test asks whether you lived in a home you owned. Someone who owned a rental property but never lived in it may still qualify — and often assumes they don’t.