Your local laws are going to prevail.

If I were in your and/or your mother-in-laws shoes, I would go to a local bank and use the free and clear house to secure a $150K+ line of credit. 

We're working with a mortgage broker local to us and he has put us in contact with Lendbase as well.

I will be doing my own research on local laws & regulations, but want to do this 100% by the books.

Any groups/meetups that i could attend in the local Houston area?

Does your local jurisdiction require you to return those fees if they were not screened? 

Buy a used book and find someone local who's doing the thing, and make them your mentor.

Hey gang - A partner and I just started a local RE investor meetup.Q: For anyone that attends these regularly or runs one....what are some of your best practices/tips/tricks to keep your audience engaged and growing?

Find a local one.  

I generally work with home owners looking for long term management, but I do work with a local broker with access to off-market deals, and he sees a lot of activity in the area.