My wife's stepfather replaced a 2 ton unit with a 4 ton unit on an 1100 square foot house. It was light a hurricane when that thing turned on. And it didn't do a very good job of dehumidifying when it was humid because it just didn't run long enough to dry out the air.
But he was a bartender, and he was always swinging cash under the table, no permit deals with tradesmen who came into the bar.
He passed away before my MIL, and when she passed, we sold it under probate rules since my MIL never completed her estate planning. That meant, no disclosures, since DW had never owned the house, and hadn't lived it in in 20 years. That came in handy because the buyer wanted some items disclosed. We replied we had no idea and were not legally bound to disclose anything, and responded he should find the person who did the work. Oh, did I mention, HE had done the work. He immediately dropped the request.