Should I sell

The stories of gen3 taxis reaching very high miles are easy to explain. They are in fleets and replacing an engine is a routine one day event. Same goes for hybrid batteries, brake boosters and inverters. The cars are great in city driving, have decent mpg, are reasonably comfortable with good interiors and have ac with the engine stopped. Reliability for a taxi fleet is fine; for a family that can't expense the repairs it is not a great car after 150k miles.

In your case, a new head gasket may last six months or six years. The piston rings are still bad and the only long term fix is a rebuilt engine. The hybrid battery replacement is a given and is the one thing everyone expected since the car was new. Toyota guaranteed them for 150k miles in carb states and they are usually repaired or replaced by 200k miles.

 

If you do replace the head gasket your car will keep going for a long time. The engine isn’t bad, I replaced my head gasket at around 140k and it’s at about 234000 now. That being said a prius will never be a wrx so I would upgrade if that’s what your heart is set on. But I would probably keep the prius if I got a sports car to have options.