How do you view buying/selling on ebay?

I sold a 1/16 E-Revo on the bay last year. It was in awesome condition. I was so sure that it was an awesome deal I gave MY cellphone number on the receipt. After the buyer receives the truck, I get a call saying it doesnt even work. I called BS because I drove the car(to bring the lipo to storage voltage) just minutes before I packaged it. He said the antennae wire on the Spektrum receiver was cut. He threatened to leave negative feedback unless I helped him out. I refunded him $50.

Heres what he got:
Month old Mini Revo in great condition.
1 week old Spektrum DX3s
4 2S Flighmaxx lipos
2 3S Turnigy lipos
1 charger
Full set of Hot Racing push rods and tie-rods
T-Bone racing bumper
3 sets of tires(one brand new)
lipo sack

It cost me about $650 for everything. Sold it for $400 shipped which cost me $25. Then I refunded the $50. So long story short, The buyer got a 2 month old, awesome condition Mini Revo with 6 new lipos and a charger and a new DX3s for $350 shipped. And for that reason I sell everything "As Is".

I know its a used truck, but if anyone on this forum received it they would have been more than happy with it, and realized the hell of a deal I gave them.

I would feel like crap if I sold him a lemon, but I know for a fact it was working and he got the deal of a lifetime. Oh well, live and learn.