How low would dealer go on an offer

Hi. I am interested on making an offer on a never titled 2013 Monterrey 26' bow rider boat with a big block Volvo with DP and nice accessories. Boat is in a show room and never been used. Original msrp and sticker is $97k. Dealer is asking $69k. In your oppinion what / how much would you offer and with a good chance of being accepted?
I am surr there is room in their asking price , but since boat is or has been sitting for 3 years, i really want to make an offer that is both tempting to them to get rid of, but attractive to me as well. I doubt if this boat will sell anytime soon since it is a 2013. Any thoughts? Thanks