We are having extensive building works done - knocking down walls, rewiring the whole place and then new bathrooms x2 plus kitchen. We've never done this sort of work before. What is the usual practice in terms of providing materials and things such as internal doors, paint, anything that might require your own design opinion. Would you normally decide on what you like and then order and supply to the builder or would they go pick it up etc if you tell them what you want? Thanks