You definitely need to be educated as a buyer on ebay, but you are fully protected.
1. Never, under any circumstances do local pickup with ebay, it is basically the same as craigslist
2. As much as a monopoly as it is, paypal protects you as a buyer and if you use it, situations like you describe will never happen and 99.99999% of all disputes will go in your favor, even if you are wrong.
Things that make me upset about ebay as a seller:
If an ebay buyer wants to leave negative feedback, even if it is fake, I have spoken to ebay, they will not do anything about it.
As a seller, I can't leave negative feedback on a buyer at all. I am an eBay buyer too, so I feel your pain, but there is not one time where I have bought something, that I didn't feel was as described, that I have not been able to get my money back.
I wouldn't say I am a power user but I have over 414 all positive feedback, I have received negative feedback 4 times and I have always been able to get it removed because I either had to lose money to an extorting buyer or I documented things so well, ebay didn't have a choice.
Even though craigslist is riskier, I will try to sell it there 1st, because once the sale is done, it's done.