This is a very common within the RV industry and with all manufacturers. The chassis of a motorized product is purchased from a separate manufacturer (Ford, Chevy, Workhorse, Freightliner, Mercedes, etc.) as an “Incomplete Vehicle” (with an established chassis serial number). When the Manufacturer completes the vehicle, it assigns a model year and a Manufacturer serial number to the coach portion. The RV industry and chassis manufacturer model years change at different times. For example, a Manufacturer may introduce the 2018 model year unit in June of 2017, but the chassis manufacturer doesn’t introduce the 2018 chassis until September of 2017.
Because Manufacturers “Complete the Vehicle” and assigns the model year, the value of any Manufacturers unit is determined by the model year of the Manufactured RV, not necessarily the chassis. This may vary by state.