When signing a contract with a plumbing contractor, make sure that model numbers are clearly indicated on the contract for all fixtures to be installed. This way, if the wrong fixture is installed, it will be easier to assign responsibility.
Many plumbing projects require a permit, especially if the work involves the main water or sewage lines. Especially when remodeling a kitchen or bath, or when adding an addition bath, be sure that your plumbing contractor has obtained the appropriate permits for the job.