Renting a room out in owner-occupied unit so that the building breaks even, including saving substantially for capex/vacancy (roof to be replaced in a couple years).

AB1482 does not permit this type of substantial change of lease terms be dictated by the owner. 

Employing this strategy helped contribute to a substantial increase in net worth.   

My suggestion is to get a Texas real property attorney's opinion before spending substantial money and even then, I believe the best you'll get is a maybe it's ok, maybe not.  

Initially I 100% wanted to keep the home, although, after learning a bunch of methods and simple formulas to determine if its even worth keeping, my confidence substantially dropped.

Of course you can do whatever you want, just be prepared to defend it to the IRS, meaning substantiating the miles were for business.

If you had a property that appreciated substantially (LTV is below 50% now), what would you do with the property?

It would be a rare situation where cosmetic repairs would take a house from under water to substantial equity.

Let's start backward and work our way to the front.LLC and credit - It takes a VERY long time to build up a financial history in an LLC to get any substantial credit line or requires you to put a ton of assets into the LLC.  

If you look at well-to-do people around, you can see that the affluent people are generally the ones who inherited a substantial amount of property.