I buy and sell on there alot with phones. Only had one problem with one phone, out of about 50 phones i have sold on there, just relisted it.
One of the tricks, is to put a big reserve price, eg...phones worth £300, put a £1000 reserve on, so it doesnt sell, then just say that the highest bidder was £10 off the reserve, so ebay thinks you aint sold it, so you dont pay there fees after you have sold it.
Works well selling cars too, as you just contact the bidder out of ebay, and do it that way. lol