Have you seen what people are asking for a 20 year old vehicle that is "expedition ready" on this site? loleven with great credit, the bank is going to want its collateral worth something. A 15 year old RV on a 20 year note isn't worth much. At 8% on a $200K rig in 15 years you still owe $82K.
I didn't mention terms, how about a 20 yr. amortization with a 5 year balloon?
But, seriously, there is more to such a note, credit score is only part of it, ability to repay is the primary concern, income over a period of time might be limited, that's where a balloon may be necessary. Loan reviews annually can bring about any call feature. 8%, lol!
Is someone making 20 year fixed rate loans on RVs that are fully amortized at 8%? Folks ought to jump on that if you find that lender.