We took out a mortgage on our old house while building our new one, as it was cheaper than a bridging loan, and the bank where we have been for 30 years wanted to do an ID check (passports, etc). We said that they could forget either the check or the mortgage, and guess what, they saw sense and realised that they did, in fact, know us. It wasn't the local branch which was the problem but some numpty in the next level up. I bet he was surprised when we duly paid back the loan as soon as the old house sold!