I purchased a 2 door full size Tahoe several years ago off of eBay. It was the biggest mistake of my life and I was very lucky to have gotten all of my money back. It did take a year and a half and a knowledgeable lawyer though...
I would recommend purchasing in person. Try Craigslist so you can go and see the vehicle.
There's no reason why you should avoid GM vehicles. The suburban is a great choice. I have a 2003 Z71 Suburban and I love it. I'll keep an out out for one for ya.