The exemption is calculated by years of ownership and designation, not by the seller's age, so a senior who has lived in University Heights for decades typically has a very clean claim, while a senior selling a property that was ever rented out or used for business may owe tax on a portion of the gain.
The sale still has to be reported on Schedule 3 of that year's tax return even when the full gain is exempt, and inherited property or a second property held alongside a principal residence follows different rules that are worth reviewing with an accountant before listing.
None of this changes based on age, only on how the property was used and designated over the years you owned it, and any accounting help to confirm it typically costs far less than the legal fees of $800 to $1,500 already budgeted for closing. Get your hand-reviewed valuation from Joel Dyck.