Tetra, all of the advice above is good, and Sailorchic's input is gold...if you get to the purchase
Mark makes an excellent point, depending on what exactly you're contemplating purchasing
. Assuming based on the engine
that it's a 30-35'er, a new engine
install may well equal the purchase price
of the boat. So following the install you'll be the proud owner of a boat is worth 50-65% of the money
invested in it, assuming you're buying
it for market value.
As noted, the general survey
is going to tell you very little about the state of the engine, other than it runs within general spec (rpm, temp, etc.) and what a visual inspection
reveals. An engine survey
would be worth the money
given there are no logs
, particularly if you don't have any experience with diesels.
If that reveals the engine to be in decent shape, just use it, maintain it, learn about it. You'll be in a far better position to then determine down the road what your needs and options are.