Absentees are THE best pool to hit on a regular basis - we mail to them monthly.  

Across ~30 applicant pools, I think I had 1 male/female mix.

Has anyone ever replaced an inground pool liner?

On the "con" side, however, for resale value, it may be lower, and your pool of buyers will be more limited, as owner-occupants may not want to rent in a high rental area.Also for resale value, owner occupants take better care of their properties, so if tenant screening is weak or declining, that could affect the value of your home.

Lack of a good labor pool. 

I wholesale in my backyard as well.

I would strongly encourage you to look for your first property here in your backyard, where you can physically visit it, be a part of any rehab, meet in person with the RE agent, home inspector, contractor, property manager, etc. etc. that you're using.

Essentially, these guys put pooled together personal money to create a fund, and I purchase and rent/sell houses for them, and I am paid in commish.

Those are great places to meet people in your backyard who are doing deals.  

I like the idea of partnerships and pooling funds but whenever you get into partnerships it can get sticky.