I never had any problems using eBay myself. more selling than buying but sometimes things start to suck either way. You just have to be patient and do your part. The best thing to do is treat it like it's a job that's paying you $750 if you do i right. Don't get frustrated or take anything personal because it just makes it harder for you to deal with the process. I suggest you call eBay asap and make sure that you talk to somebody to get your concerns noted and have some type claim number for the next time you call.. be patient, wait the exact time frame, and follow through with the process as you are supposed to. Make sure to get it noted again and take names of who you talked to. Do the same thing with your credit card company and treat it the same way.
The main thing is to get your money back and second is to not to let it bug you out.
Everything should turn out fine... Hope you find what you are looking for.