Builder estimate for renovation work on our house was £7,500. Work included removing window & replacing with patio doors, removing two internal walls, fitting insulated plaster board in bedroom, laying hardwood floor, converting a bedroom into a bathroom, including external pipework.
We paid an initial £5000. He took over seven months to do the work, with very long, unexplained absences throughout (the longest was 9 weeks).
During the work, we also asked him to fit respatex in the shower, board out the new bathroom with plasterboard (uninsulated), he added coving in the kitchen and s