Once you have shortlisted a few contractors you like, get bids from each one. Discuss the scope of the project and lay down your expectations. If you have blueprints, show them the plans. Let them know your budget and ask them for a full quote.
To compare the bids effectively and make the best decision, ask each contractor to provide detailed information about the labor and material costs, as well as all other expenses involved.
When a particular bid makes sense to you, start the negotiation process. Ensure that the bidding document contains all the details discussed, and you’re comfortable with the terms and conditions from the start.