Like Randy said, you'll certainly have to issue TIL disclosures by mere fact that it is a consumer loan.
If the loan is for more than 12 months, then taking their principal dwelling (regardless that it is a recreational vehicle) will also trigger ATR / QM underwriting (1026.43) requirements. Further, I imagine the pricing of such a loan will be surely higher than a stick-built home, likely triggering it as an HPML (1026.35). If so, you'll need to escrow for personal property taxes and insurance (even though there is no real estate). It could even end up being a HCML (1026.32) too, subject to numerous rules.
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Me, Type A? Maybe - I'm not done analyzing it yet.