Why it matters
Buyers inherit unpermitted work. The municipality can require a retroactive permit, stamped drawings, opening finished walls so inspectors can see concealed work, and upgrades to current code. Insurance can deny claims arising from unpermitted work, and unpermitted electrical can trigger ESA defect notices. "Renovated" without "permitted" is a claim, not a feature, and a freshly renovated older home with no permit history is the paper-trail version of a flip.
How to spot it
You can't see it in photos, you ask. "Which renovations had permits, and were they closed?" Your lawyer can request the municipal property file; ESA can confirm electrical notifications. Visible tells that raise the question: mismatched breaker brands in the panel, amateur drywall transitions, a basement suite in a house that never mentions permits.
What it costs
The permit itself is cheap and that is the trap. A Toronto building permit starts at $215, and work already begun carries a further 50 percent of the permit fee on top, capped at $29,457. An Electrical Safety Authority notification starts at $92, a residential alteration is $46 to $201 by outlet count, and anything the schedule does not cover falls to $177 an hour. Homeowner performed work is inspected at a higher rate than a licensed contractor's. The expensive part is none of that. The building code requires inspection at stages that happen before anything is closed in, framing before insulation, insulation before wall board, plumbing rough in before it is covered, so legalising finished work means opening the walls again. No source publishes a price for that, and this card will not invent one. The statutory maximum fine under the Building Code Act is $50,000 for a first offence by an individual and $100,000 after that, which are maximums on conviction rather than typical outcomes.
What to do
Order a building records or permit history search from the municipality before your condition period runs out, because a title search will not reliably show it: sellers are not required to register open permits on title. Run the electrical question separately, because the Electrical Safety Authority is a different regulator with different records, and ask whether a Certificate of Acceptance exists. Note that its Electrical System Safety Assessment explicitly excludes anything concealed in walls, so it cannot clear in-wall wiring. Price the remediation rather than the permit, and get a contractor to quote the destructive inspection scope specifically. Make it the seller's problem while you still have leverage, because once you are the registered owner the City's position is that you own the obligation.
Education and triage, not a home inspection. Casaroo raises the question when the evidence pattern suggests renovation, it cannot see permits and never declares work legal or illegal. Your lawyer and municipality confirm.