My 700P never had head reception problems. As for the buttons not working, the green button is considered by a few here and there as an extra button - I never used it for calls, I assigned it to do other things and the phone function can be assigned to another button. However.....
Have you looked at the Palm website for Versasmell (
http://www.palm.com/us/support/downl...reo700pverizon).
From what you have told us, I am positive the original owner dumped it on you without being totally honest; hence the reason I would never consider a used device of this type.
The Treo 700P is an excellent device (I had one and after a bit of work, it was a very solid device). May I suggest if you are in a position to maybe switch providers or talk to someone about getting maybe a Centro or a refurbished Treo from a reliable source.
Ben