If your web developer is the only vendor you have a problem with fire them... if you have problems with many of your vendors best to look in the mirror before you clean house.
I took a client on one time that I had some reservations about. Some people (especially entrepenuers) can be hard to read. Some of the most successful entrepenuers are also the most eccentric. There are times when it is hard to decipher eccentric from full of "it."
At any rate I ignored a red flag I shouldn't have and things didn't end well for me. The one red flag that popped up that I should of paid attention to was the client, while always indicated he was happy with my work and direction, complained incessantly about how they couldn't find competent sub-contractors and/or vendors. What this says about the client is that they are the problem. Either the client doesn't know how to go about selecting vendors or they have run all of the good ones off. EIther way, down the road, you will probably end up being an "incompetent" provider as well.
I have to own my mistakes. I should have turned the job down or severed ties sooner. Whether you are a web developer or not, this scenario probably applies to many small business owners.