So a $20K repower may only be worth $5K to the lender, even right after work is completed. On older boats it may have no value at all. .
I think it is worse than that.
My saying is that buying a boat is the most efficient way to convert dollars into dimes.
A brand new Catalina 309 out the door ready to sale costs about 120,000
A 1985 Catalina 30 costs about 12,000.
If you put a new motor in your 1985 boat that costs 15,000 with new tanks, prop, shaft, cutlass etc you 1985 boat might boat might be worth 20,000 if everything else is clean.
Not dollars to quarters, dollars to dimes.
Now the really scary thing is if you live in a sales tax state like ct you have to pay 6%+ tax. If you buy the boat keep it for a year then decide to sell you have to pay the broker.
You pay 100k for the boat 6k for tax and 10k to the broker to sell.
If you sell it for what you paid for it your 100k is now 84k.
But you almost certainly will have put some money into the boat the first year. Also you probably will not get exactly what you paid as the boat is one year older so a 20% loss in principle is pretty much a minimum.
So you better keep the boat you buy for a long time.