Confirm charges for parts. Most plumbers keep basic parts and supplies on hand, but sometimes they have to buy specialty items after starting the work. Be sure you know what the markup is and how you'll be charged. The plumber may ask that you choose and purchase decorative items such as faucets in advance, with his or her input about specs. That way, you can ensure the look you want and avoid time-consuming exchanges.Be clear on who cleans up. A good plumber will never leave you with a sloppy work area. However, if the project necessitates prying out tile, pulling off baseboards or other structural damage, not all plumbers can or will make those repairs. Ask beforehand whether this is the case, and plan accordingly.