You can ask as much or as little as you want.
Another way of answering the question, is that there is no way to give an intelligent answer to that question unless we know a great, great deal more: where you are selling it, a very detailed accounting of its description, what venue you plan to use to sell it, (and if the venue involves the internet: how good are your photos, and your description, shipping, etc), how long you are willing to hold onto it, how good you are at selling it personally, and probably quite a few other things that I am not thinking of.
Another way of answering is to say that the forum rules indicate that this is not a free valuation service.
Another way of answering it is to say that I've seen prices from about $10 and up for comparable items.
Hallo.
First, I think that the answer given you by leif ericson is probably the best you could find, given that he took the time to answer you at all.
But answering your question: find out what this couch goes for on firstdibs.com, than divide the price by 3. It will give you a realistic price to start with. It looks in great shape so you won't have troubles in selling it, but the higher the price, the longer it will take your friend to sell it.
cheers,
Ernest
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