@user701 it depends how many holidays they take
my builder used to take holidays every half and full term. His wife was a preschool nursery teacher so no work to mark in the holidays or lessons to plan. They used to go to the same places ie had a small villa complex they visited every May in Spain etc so he was basically away from home for about 10 weeks year! His Uncle is a financial advisor and told him never run anything except your wages through your books, hence why the client pays the subcontractors directly. It wasn't a tax dodge, he was just smart, renovated a shitty house into an incredible house because he knows everyone in the trade so was able to get an amazing house for a lot less than if he had bought it like that.
£85k salary is a lot of money for one person, yes you can choose to live in an expensive area or go somewhere where your money goes further. It also depends when you bought your house, he bought his over 20 years ago when house prices were a lot more reasonable. They never needed childcare or summer clubs because his wife was available.
I am in Yorkshire, these are the rates for my trades that I have had in the last 6 months, plasterer £250 a day labour (doesn't look like he has plastered because his clothing is pristine, the walls are like glass and no mess ever he is incredible) I pay for materials, electrician £240 a day labour, his son is also a spark, works on new builds so easier as first fix with completely empty walls, he gets paid £250 a day, my spark could do the same but he likes the challenge of a completed home, he is incredible at fishing cables in walls.
Being able to find prices isn't like the old days of the yellow pages, you can find loads of businesses online, search for products, find handymen/builders who can put a steel in. We have a local businesses booklet, we always try to get local people in, no national companies. When we had all our windows replaced we went to a company that makes them 2 minutes down the road, no middle man ringing up places getting prices from those manufacturers.
Some costs are insane, but shopping around and not being swayed by brands saves money overall. Lots of builders overprice jobs they don't want. Find smaller businesses, look around at business parks, who is on there? Find smaller bathroom companies not the high street named ones but the local ones who have been around for 20 years.