Can't you just go and collect your Elna and sell it on your own? Selling on consignment at a shop will probably cost you more than the 10% you were quoted anyway. If the question you were asked was "what will you take for it?", odds are that they will sell it for as much as they can and pay you only what you told them you wanted less the 10%. They may, in fact, be making much more than that in the end. It's standard parctice and is why they ask the question in that way. And do you have to pay them for the evaluation of the machine on top of that? None of that, nor the time it has taken thus far, is out of line for the shop owner.