Consignment...Seller won't budge off of asking price.

If it feels right I would say don't let the money separate you from a nice sounding RV. If it doesn't feel right and the money is vital, "cash is king" and I would walk in with the last cash offer, but it would be my last cash offer. And I would be nice about it and raise my offer a little and hope they might see way to helping offset tires expense. I do like the idea of thinking about, what if it is sold before you get back to it...how will you feel? Good luck!