Need letter from employer that either says they allow remote work or the hire is for Texas location. 

HELOCs are much tricker than a closed end second - they don't typically allow you to close in an LLC and they are full doc qualification, meaning your FICO, employment history, income, DTI etc all come into play.

For example: A small town has a large employer close down.

Solid employment history.  

Real estate's "gross rent multiplier" is Wall Street's "sales to revenue",  "cap rate" is roughly "P/E ratio".When evaluating markets and investments I tend to start with GRM (or lazily the 1% rule), then attempt to return a cap rate based on assumptions about costs, then I work my way to multiple years of projections (assumptions about inflation, amortization, tax benefits, etc), and if I am partnering with one of my smart friends I have to pull up an IRR (internal rate of return).I also look at regional employment levels, median income to rent ratio in the zip code etc. 

I use the 3x rent for my first barometer, steady employment, good credit, and of course 3 years of rental history.

Our market is stable with strong job growth from major employers moving and developing here like Meta, Intel, Amazon, etc.

But if employing your family works for you and for them - great, go ahead.

I'd have them sign my own lease on renewal and I'd make sure I had enough information on them so I can go after them if a legal issue arises such as employer and other similar data. 

Just food for thought here, all the hype around subto lately got me thinking, it's not even a strategy I typically employ but like to have in my back pocket in the rare case when it makes sense.