1. If you can, ask builders who have been recommended by people you know who were happy with the work. 2. If you dont know anyone personally, then start with the fmb (federation of master builders), who have a searchable database of builders who have been vetted and approved. 3. Have all your information ready, building regulation approved drawings, and a full specification of the work you want carrying out. The more detail you provide the less provisional sums you will end up with in the...
