We had one when I was in HS. We had a regular toilet and a claw bathtub in the house. The out house was used when the indoor toilet was in use. One summer my dad gave us a project to dig a new hole for a septic tank. No vault was to be installed, just a large hole. We did that and the regular septic tank overflow problem was solved. I'm not sure if there was no pumping service available or my dad was just using free labor to solve the problem.
We're on septic and drain field here but the county requires an inspection every 3 years.. Anyway, I know about outhouses. Arizona 1964.