So that $15.2K is for a remanufactured engine or to remanufacture _your_
engine?? Cause I thought doing the latter (tearing it down and
replacing most of the parts) was the 'usual' method, and I thought (had
been told) that around $10K for everything for a 235 was about right.
(No, not told by the FBO that's selling the plane.)

Factoryengines.com lists O-235s for 15.2k, 17.9k, and 22.5k (overhaul,
remanufactured, and new respectively). Plus, you will have install
costs and have accessories to overhaul or replace. You could hit $20k
easily for an installed overhauled engine.

-Nathan