We have 2000 hours on a 17 year old
Yanmar and it runs like a new engine. Our 8 year old
Perkins has only 1000 hours and it's flawless. Neither engine requires any additional
oil between changes. I'd expect both engines to out-live the two of us before requiring a rebuild.
You're comparing 46 boats
for sale, that's ridiculous. We recently replaced a
water damaged
generator which has a larger
diesel than many sailboats, the total cost for replacement was $12000USD. Worrying about a few thousand hours on a
diesel is insignificant in the whole scheme of things, especially when a set of
sails can cost much more.