This is a very personal question that is difficult to answer. 

Be prepared to follow up multiple times, using different forms of communication—calls, emails, and if possible, in-person visits to their office.

Account holders can't take any write-offs personally for investments made in the 401k.

Just my personal opinion - get a mentor or a person who already has good experience running STR business, preferably in your area (but not 100% required). 

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

Are you able to go there in person to build your network? 

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)).

This person (not Blake capital) was trying to bully me (wrong move).

Ask your employer if you can have your pay split up into three deposits, one to investments savings, one to your checking account for personal use on a daily basis, and one to an emergency account you can tap into so you don't have to tap into your investment savings.

Find someone where there is a personal connection and at some point your relationship now or later can benefit the mentor.