Two fellows arrived in an open-bed pick-up truck. They had tools, but no plumbing supplies at all. They new they were coming to install a new toilet (provided by me), and a new sump pump (to be provided by them). I have no idea whether or not the gentlemen were qualified plumbers.
Hopefully the work was done properly. So far so good (done 3 weeks ago). My beef is with being charged $120/hour while one of the fellows went to our local Home Hardware to purchase a sump pump, a wax seal, a check valve, a toilet supply line, and ABS pipe. (Coreys installed a new sump pump just 5 years ago; I was proactively replacing it.) In addition to paying the labour rate while one person shopped and the other had almost nothing to do, the 5 items purchased were marked up by between 11 and 27% over retail, despite Coreys Plumbing paying less than retail for the products (as confirmed by the hardware store).
If you chose to use Coreys be sure to buy the items needed yourself. Save labour time as well as price gouging.