Hi Jamie
Got to agree with Ken's post on his comments regarding selling and buying on ebay, with the added comment "it depends". Your post does of course touch on that dilemma that seems to affect most modellers I know or read about on web sites.....too many models and not enough time to build them all. Over this last week or so I've started to say to myself am I a Model Kit Collector or a Model Kit Builder
Of course the fact that model manufacturers keep bringing out kits you simply "must" have or didn't realise you "needed" till it came out doesn't help.
But back to your question regarding ebay selling. Unless the kit is something rare or out of production then as a buyer I look to pay around half the price of a kit (second hand) it would cost to buy in the shops plus postage. This has worked fine for me, but I do set myself limits and am able to walk away if a price goes higher than I'm prepared to pay. I say to myself, never mind another one will come along soon enough and you'll probably get it cheaper, and in most cases it's true.
But then again I've seen people bid up to and pay the virtual retail price for a second hand kit which is still available in the shops, and in some cases actually more,
but like I said it depends.
So whilst I have benefited from those modellers who have brought large numbers of kits and realised they will never build them all or need to sell for another reason be it divorce, relocation, etc. I have myself have become exactly the same as those I've purchased from...too many models and not enough time.
Right now would be a very good time to sell, and as an "ebay watcher" I've seen a rise in final auction winning bids prices just lately, but not after Christmas and towards the end of January when the credit card bills start dropping through the letter box and people realise the true cost of Christmas
I think for many, including myself, the realisation that you have simply too many models too build, to the standard you want within your lifetime finally dawns. You then decide either to stop buying any more and concentrate on building what you have or if your collection is so big, sell of the ones you think you "might" like to build and use the money and time to build the ones you "must" build.
I'd suggest you give it a try with one or two kits and see how you get on. If I could make a couple of suggestions.
Ensure your listing ends at a good time to ensure plenty of punters at their screens ready to put in that last second winning bid. No point in it ending at 2 am in the morning on a Tuesday, rather in the evening, probably at weekend would ensure maximum return.
Remember ebay takes a percentage of the sold price, not the postage costs so don't offer your items postage included because you'll be paying ebay commission on what it costs you to post the item, thus reducing your "profit" even more. Some see this as a way of avoiding high ebay fees by putting a huge postage price but charging little for the item. You see this done from sellers in China. They sell the brand new kit at a starting price of 99p (UK money) but charge £14.00 postage. Naturally ebay take a dim view of this and will suspend your account if they feel justified.
Why not do some research before selling. Check out ebay and see if any of the items you have are listed. Put them in your "watching" list ebay provides and then see what they finally go for to give you some indication of what you may get for yours.
Finally, you might want to advertise them for sale privately, most forums have Buy and Sell sections. In that way you don't pay commission to ebay and don't have the "gamble" of it not realising the sum you hoped for. This works well from what I've seen especially with buyers and sellers based in the same country, high postage costs being a major factor in putting off sellers in Europe from buying for example.
regards
Alan