Paul S. agreed, thats why i never have it... fortunately most of the rentals have nice hardwood underneath the carpet that can be sanded and restored... saw your earlier comment about floors and I have acquired a property with solid floors that needed remediation because of pets... i guess if neglectful owners let acidic dog piss sit long enough damage is done

When I first started, I found out the hard way about title clouds, IRS liens, buying land that didn't have legal access, water issues, soil issues, etc.

I said  jacksonville in my original post as my city doesn't come up Well I don't know about you, but I'm bringing at least 10 years worth of food, water and toilet paper supplies down into my nuclear bunker underneath my house right now!

So you can’t build permanent structures underneath.  

I plan to hold and operate the property for at least another 5 years.I'm leaning towards the regular dwelling route but one architect told me going the regular dwelling route might require Baseline Hillside Ordinance (BHO) compliance, hill/slope grading analysis, a soils report, hiring a fire consultant to design/engineer fire sprinklers for the SFR, and having a structural engineer design/engineer the entire house (SFR + basement).

I don't know the laws in Texas, but here in Tennessee you can't manage another property professionally without a license or working underneath a licensed broker.

you have some of the worst soils I have ever seen.. its called Yazoo Clay as in Yazoo city MS.. this clay expands and contracts like no other..

To me, it seems like all nail heads should be underneath the other shingles that overlap. 

You say the "house plumbing works wonderfully"; with the drains full of roots and soil, it's only a matter of time until they start clogging and creating sewage backup in the units, so I would say you have no choice but to fix this now, and to fix it properly.

A big factor has to do with what type of soil the slab is poured on.