I have one (only) earth contact home as a rental. I bought it because it's close to the house I live in, it had a storage building, and three acres, and I bought the whole package for what a regular lot with utilities would cost. That's where the good part ends. The house has a lot of space but it was poorly constructed and it is a maintenance nightmare. It's worse than owning a mobile home when it comes to finding replacement parts for anything.
I have had the cobbled-up combination gas furnace/heat pump rebuilt into a normal gas furnace and central air conditioner unit, with factory standard components. It is a lot more reliable that way and parts are readily available. I have a really good HVAC guy.
The electrical service is another cobbled-up mess that I am slowly getting converted to standard components. The house got struck by lightning last year and part of the service melted along with the tenant's Uninteruptible Power System for their computer. I got some more pieces converted to standard house wiring components as I had it fixed.
The plumbing is cobbled-up as well. The sewage lagoon was a small pond built up with a ring of gravel. It leaked, of course, so I have put in a new lagoon. The sewer inspector, a gorgeous blonde in her late thirties, wanted to put my contractor in jail because he wouldn't show up for inspection appointments. I don't know what that was about, and I don't want to know.
The roof needed replacing a couple years ago, and we had a reputable contractor friend put the roof on. He called in the middle of tearing off the old roof to tell us that there were two broken rafters and a spot where a rafter should have been but wasn't.
On to the ugly part. The tenant told me that a corner of the front wall was decayed and the house was about to fall down. Our structural engineer said there was some decay but no immediate danger and no settling. So today my son-in-law and I tore out the interior of that section of wall to replace the decayed bits. It was immediately obvious that the decay was related to the former roof leak since everything was dry in there. Did I saw dry? Holy moley! There was thirty-year-old sprayed in foam insulation in there that had dried out. Part of it was in soft chunks, and part of it had turned into powder. We scraped the stuff into trash bags and vacuumed up the stuff until the shop vac filter plugged up. Then we dumped the powder into more trash bags, shook the powder out of the filter, and vacuumed up some more powder.
There was only three feet of decayed wood in the wall, so we replaced that and put it back together again. We also straightened out a dogleg in the wall so it's one section of straight wall. Two guys, seven hours each. I am tired and sore, and when I blow my nose I get mud.