To employ contractors and workers, you have to obtain references or get to look at previous work of applicants and prospects. It is not impolite or being impertinent to ask for references and asking to see previous projects prior to hiring. This is standard when trying to employ people for house building projects. Moreover, it is also smart to get more than one bidding from contractors.
When looking for a single do-it-all contractor, at least fifteen percent markup is enough to accomplish the work and may look for at the most five prospects to bid. For minor work you want to handle on your own like a new bathroom or kitchen or house building less than five bids are adequate like two or three. It is just important to guarantee that all considerations are covered and that the amount they make estimations of such as for plumbing and other stuff that had been chosen are practical.
It is also standard for house building to obtain written quotation or estimation. No one can say but it would have saved others a lot of exertion and aggravation had they had the terms and costing in written form. If the contractor is agreeable with the written terms and costing and had affixed signatures to the contract, he and the homeowner can no longer protest even a little about the contract later. Both sides have to make sure that there are no more minor adjustments needed in the contract. Once it has been signed, there is no more chance to do any adjustments later.