My old house was built in 1730, the only cavity was the living room . . . Walls were over a foot thick
THe current Zefarelly Towers is the first house I've had with cavity walls!
Do your own homework Re build
iggest hidden expense I've experienced is my first flat which was a leasehold . . . . Freeholders and managing agents had a license to extract money. . . That was 25-30 years ago.