All kinds of life coaching going on here....
Regarding buying a RV 2-3 years from now and storing/maintaining it for basically another 10 years before it's fully "in use", I would analyze that scenario more closely than floor plans and financing arrangements.
- Storage. Unless indoors, in 10 years the sun is going to take it's toll on that "brand new" RV.
- The depreciating assets comments are true. Do you want to eat the depreciation and most of the interest payments while not really using it and start off with a 10 year old rig that you just spent roughly $190k on for a $120k purchase (I used 20 year loan, 5.5%, $120k loan amount, paid off in 12 years)?
To that point, don't buy anything in 2021, invest/save your $1000-1200/mo for 10 years. Have the better part of $200k in cash to buy a 10 year old low mile (stored like you plan on doing) for like $50k. Spend another however much on a trailer or little rv for your infrequent vacations over the next 14 years.
Then when you retire you can have the same RV you're plannin on buying in 2021, pay cash and have an extra $100k in cash leftover.
If intent on a new RV, I'd wait until it's time to use it full time, go big spender on it and if you don't get it paid off, you'll still have $100k of play money and can let the kids, bank and executor deal with it when you croak.