I list my books at BIN, for about the 3rd cheapest. There is no point in having a store unless you are listing BINs. Except maybe for the odd loss-leader auction to draw people in.

I sell, mainly, mass market paperback fiction. A store with BIN suits me as it only costs 5c per month listing. And the last 2 months I have paid for about 300 of 900 listings; which more than offsets the store fee.