
I sold a couple of things for the other half last week and have had a bill today for more than 20% of the selling price. Seems a bit steep to me.
TOO Much 
Its a rip off nowadays. But there isnt anywhere else with such a large audience to sell car bits online.
http://pages.ebay.co.uk/help/sell/fees.html#fvf
If you're not a top rated seller & getting discounts then it's (roughly due to minimum amounts, ad fees etc.) 10% to ebay & a
further 4% to Paypal (more if it's for small items as there is a static charge b4 the % goes on).
I can't see anyway it could come to 20% tho' unless you've also had a load of listing fees for stuff that hasn't sold or
something???
Whenever selling on ebay I always reckon costs of a minimum of 15%, that way you have a realistic expectation of what you're likely to actually
see, unfortunately many sellers simply don't understand the fee system & frequently sell at prices where they will make little or no profit,
hence buyers then have an expectation of unrealistic prices.
Hence why myself & many others are happy to offer discounts if we can sell off ebay!!! If anyone comes up with a realistic alternative to ebay
with even a marginally better fee structure they will do very well indeed! Unfortunately I think the only real competition at present is Amazon &
I don't know from personal experience, but I've been told their fee structure is actually worse!