Personally, I wouldn't offer SubTo or a Wrap, For reasons I've written about fairly extensively. https://www.biggerpockets.com/forums/70/topics/1227199-the-m...However, I would sell on "Lease Option" and that may work for you.

Tell me - someone selling their home to your son, Subject-To - is this a person who has made good life choices? 

I have personally used the BRRRR strategy over 40 tiems my self in Memphis.

I was thinking if I can talk to my neighbor about sharing the cost (I, the landlord, personally provide labor and my neighbor provide material (e.g. fence pickets)).

A contract is only as good as the person enforcing it.

CPAs generally have more knowledge about general accounting but it is ultimately up to the individual person to take it a step farther to get more specialized.

I personally believe that a better way to jump into mid term rentals is to take a course on buidling a property management company or cohosting business where you bring your skillset to the table without the intial investment into all the furniture and leases.

Any recommendations on Houston REI groups that meet in person or virtually?

Be that person who set's up some STR's there, runs em there, and really caters it to the US "bucket list" tourist. 

There is an amount that you can distribute from an IRA account to purchase a personal residence.You then might be able to turn the personal residence into an investment property.Best of luck.