Records matter first because they are the easiest thing to lose track of. A permit for a finished basement, a secondary suite or a major renovation is what turns a guess into a documented improvement, and it is much easier to gather that paperwork calmly now than to hunt for it once a move is already underway.
The valuation matters second because an online estimate cannot see any of that paperwork, or the condition of the house, or what a specific street actually commands right now. A homeowner working against a deadline, retirement, a health change, downsizing, needs a number they can actually plan around, not a placeholder.
Doing both before you have to move fast is what turns a rushed sale into a well-timed one. Get your hand-reviewed valuation from Joel Dyck.