Nice work. Being willing/able to take on more challenging DIY projects definitely helps with getting the most out of a car. I imagine this job at the usually quoted prices means it's trade in time for many owners.
Or try to sell it at a premium price, at least from what I see being listed on Craigslist in the Bay Area, and pass on the problem to the next person, most likely someone wanting to drive for Uber or Lyft.
Like this person?
"One owner only, the body and interior of this car are in good condition (normal wear and tear), clean title, regularly maintained and cleaned, CARFAX report available.
This car did have a head gasket problem in the engine which has been worked on by an excellent mechanic. The head gasket was causing the car to lose fluid and coolant was entering the cylinder. While it is not possible for the head gasket to be replaced without replacing the entire engine, the mechanic fixed the problem with Blue Devil head gasket sealer which seals the head gasket so it is no longer leaking fluid. This car is fully functional and drivable, but it is ideal for commuting/local driving, not long distance driving. Also, this car needs to be driven gently without aggressive acceleration. Mechanic's contact information, detailed information on work done on the car, and CARFAX reports all available upon request.
Great for local commute, first car for teenager, transition car, etc.
(2010 Prius with 125K miles)