On a recent remodel job we had to have a plumbing contractor install shut off valves for the toilet and the sink faucet. He was already there doing other work but he charged $40.00 per valve. Seemed high to me.And I am not sure why we have to install them. When you put in a quality faucet that lasts for 5 years or so then you go to replace it the shut off valves often don't work completely. Is it necessary or a trade secrect to get more money from us? Maybe the water shut off valves in places other than St. Louis last longer but most I see don't outlast the faucet.