The thing I think a lot of people end up thinking, is that they saw an item go on ebay for X amount, so they say 'Maybe I should sell mine if they are worth that much!!!' However, ebay doesn't work like that. So many things affect the price
1) The listing - lots of photos and a nice clear description with an account of flaws with the item helps
2) The cost and availability of different shipping options
3) The condition of the item, if they are usually battered and the one being sold isn't, that'll push up the price
4) The feedback of the seller
5) What the market for that item is like - if one hasn't been on ebay for ages, and then someone lists one, there might be a flurry of bidding activity. If a few have been sold recently, the price that they go for drops, as some of the people looking out for one have won auctions and are no longer in the running when that item comes up.
Its very easy for me to think, 'Jeez, that scandoubler went for two hundred quid, maybe I should sell mine, I could do with the money', but chances are I will be disappointed...
