When I see the phrase "Make an Offer" my interpretation of that is the Seller is attempting to encourage dialogue. The person wants to sell the item, knows that it is used, but feels that his item deserves consideration at a specific price but is also open to considering another price. I see noting wrong with this. I take no offense when I receive a price that I think is too low. I have sold at least 2 or 3 items where the buyer started out lower than I expected and we were able to eventually come to an agreement on a price that we both felt was fair and we completed the transaction. Its called Negotiations. Neither party gets exactly what they expected but at the end of the day each agree on a price that they both are satisfied with.
well said