Some proposals simply say to paint the walls and ceiling and never specify the number of coats to be applied. If the colors are similar enough, it's possible to get away with one coat of paint and not discount your pricing. No matter how hard you try, tiny, pin-sized air holes will pop exposing the original walls. This may not bother you if you can't notice it, but principally speaking you should have paid your painter less for the work.
House Painting Denver 80220
I was a painting contractor for many years and never asked for a deposit upfront. A good contractor should have great credit with his suppliers and an even better contract if the deal should go south before the job is done. Get to know your customer and explain how each paint covers so they understand fully before you have to apply 3 or 4 coats. If you didn't bid your job right and the client has already signed the contract then that is on you not the client. Yes I haven had to eat the difference but the client was happy and a return customer for years so I made up for it. http://www.youtube.com/watch?v=b6_WEt9k_Hw&feature=youtube_gdata
As you walk through your lighted rooms (preferably day light) see if the new coat has light spots showing the precious paint. This is call "bleeding through". This means that there's only one coat of paint or the paint was diluted or the trasition of colors were from light to dark (or the other way around) and primer was not use or the painter is inexperienced.