include in the bid for the whole job,labor costs,emphasize mats provided AT COST,some guys charge hourly,,,give an estimate,get some income, and mark up what he gets from the supplier,like paying double,or they do a couple no shows for 2-3 days,or a week,tell cust he had a problem w materials,
sounds reasonable,be sure & take pics,before & after all done.
anon cited items belong in your labor bill,a cost of doing business,if the cust wants a bill reduced ,note his wish on the final invoice w signature,knock off 50 bucks,
30 or 60 days warrantee of the work & mat's is reasonable.
just do careful color matched caulking,make sure all plumbing is proper tight & running right.
after all done,give the guy a courtesy call in a few weeks to ask hows the work I did.
if you get favorable words,the guy would be a good reference,a built up resume.