when boat engines break they dont fall out of the sky tho.. lol
That is the absolute truth! We've responded to quite a few redbirds. One common theme on the "experimental" planes is they often use converted car motors because they are much less expensive, and it shows

.
Personally, and this is really only my opinion, I look at outboards the same way I buy a car. I would rather have a car with 150k miles on it with the original drivetrain that still functions well and has good compression, then a car with 80k miles and a rebuilt engine.
For a few reasons, first you never know how well the motor might have been rebuilt, or who did it, and I personally believe it's hard to beat the factory. Also if a car has high miles but is in great condition then that means it was taken care of. The car with 80k miles may have less mileage, but might have been dogged around which means other parts will fail soon too.
Rebuild it on the cheap and sell it, or use it, but I wouldn't do it to make a profit. Just my $0.02.