I find that the cost to erect a manufactured home and the proper foundation is a quite high price. So don't underestimate those. As for a new MH, the dealer is extracting the market price with his "incentive" built in. Likewise, if you use the NADA properly, in place, I'd be loath to add anything to the price since it should include that. However, if you do then you need to extract the RCN to add to the EP and with NADA you rarely have direct access to the same model and configuration on the manufacturer's website and are working fairly blind using other units as a proxy. Therefore, I think you risk over-estimating the total cost of the MH and under-estimating the cost to move, set, and erect the unit on site with a proper foundation. Therefore, if I have a manufacturer's cost or the original cost (from the owner) I can adjust the RCN based on the Historical multiplier of NBC or M & S. In my opinion, M & S and NBC tend to over-estimate the RCN of manufactured housing compared to real costs. So I pay the freight with the NADA book for manf. housing and do not rely upon M & S or NBC because, as I stated, I don't trust their numbers. They are too high.