The term MSRP, in most other industries, stands for Manufacturers Suggested Retail Price. In the RV world, that MSRP number is set by individual dealers. It is based on what the dealer actually pays for the unit, dealer installed options, shipping costs, and dealer mark up (profit margin). Some dealers are a little more greedy than others. Manufacturers have little to nothing to do with RV MSRP's.
You could see twenty trailers, all the same make / model / options, at twenty different dealers, with twenty different MSRP's, and they could vary by as much as 10 - 15 thousand dollars.
X2.
My wife was the book keeper for a Skyline RV/mobilehome dealer some years back. This particular dealer was a high volume dealer in the southwest. Due to their high volume they were offered a lower cost price per unit than "some" other dealers. No one but the dealer and his financial mgr knew the price the manufacturer cut for the dealer. Non of the sales people knew the actual cost the dealer had in the unit.
Oh sure the dealer and the manufacturer used the old at or below some type of invoice price gimmick such as factory invoice or dealers invoice or in some rare cases a MSRP number of some type. Folks like to hear their getting a 25-35 percent off a MSRP or some type of invoice price.
We always buy used units. Many RVs (not all) can loose 1/3 of their value the first couple of years