Its all in what you want, I bought a 1984 Sea Ox for $3000, in fall of 2006, I added a hard top,$3000 all new electronics, $2000 and now a 2005 4 stroke at $8200, miss and the boat stands me right about $20,000
There is nothing like having all new! Man I just turn the key and no worries all day (I Hope!!)
Joker if you love the boat and sure you are keeping it, then go for it! If you can trust the guy and he does a complete rebuild the right way, its worth it!
I just looked at a 20' foot Mako brand new, boat motor trailer, nothing else $40,000
You can do a lot with that kind of coin!!
Good Luck