The Honda carbs are even easier to do than the others you mentioned.

BTW, 2 hours to remove and clean a Honda carb on a 20 HP? Find a new
tech. That should only take one hour, in my experience.

Do you have an air compressor? How about carb cleaner, "Gunk".
Dismantle it, soak it in GUNK, wash it clean in gas or varsol, clean
all your circuits (idle, off idle) using a thin wire to snake through
the circuits. Blow it all clean with compressed air. A new kit, I am
guessing, should be about $20.00. Yeah, and a service manual will save
you hours of guess work. I'd get one.

Also, I am not sure what your tech is talking about, but if you
stabilize the fuel in the winter, spring start up and run should be a
breeze and this should not be occurring yearly.