I have purchased my MAMIYA AFD camera plus a couple of lenses (80 1.9; 45 2.8) and film backs, all were in excellent condition. I never had any problems with any item. Most recently, I a bought an EX+ Sekonic L-758DR--- saved a lot of money with the 11% discount and free S&H.
The only time I used EBAY was when I purchased a mint YASCHICA ELECTRO GSN for a great price. For major purchases I rather go with reputable dealer like KEH that offers a 6 month warrantee.
Peace of mind if priceless.