DSDP Don wrote:
Each state is different and you need to know the repercussions. I know some states do their taxing on the price of the new coach, minus the trade in, since you already paid the tax on the trade. In California, they don't care. If you buy an RV for $100K on Monday, you pay 8% tax ($8K). If you trade that coach in on Wednesday for a $150K coach, you'll pay another 8% on that purchase ($12K).
That is "sales tax". The OP is talking about the DMV tax/fees. The sales tax (or "used tax" on used vehicles) is a one time hit. The DMV fees are yearly, and in CA include the "registration" fees and the "License" fees, as well as a few more small added fees. Both the Registration and the License fees are based on the vehicle's value, although I'm not sure know how that value is determined. The "License" fee is the fee that is actually considered a "tax" (and is therefore tax deductible).