True no cut & dry answer........... From the dealers stand point most get a discount the more trailers / RVs they buy..... but then comes overhead ......how many employees, cost of taxes, their building, electricity, advertising, etc. etc. etc......
Our little dealer has 3 employees, is in an very old car dealership, & in an area with a low tax rate.(They see a lot of campers) or Take a Camping would with a several million dollar building, many employees probably at least 30, do a lot of advertising, sit on high dollar property, & are usually in a bigger city with higher tax rates & etc............
As far as the manufacturer........ the unit they are building makes a difference is it popular or unknown....... Why is a 36- 40 Toyhauler (Different make similar features) Run MSRP from 35-125K ?????????? Again labour rates of the area, taxes, materials all come into play.........