I would push for very low or no money down but having a Realtor that needs to have their fee paid it may still not work.Look up the owner if possible through truepeoplesearch.com and call them up directly.

Are there specific factors you look for in an area to make sure it’s a good fit for this type of rental setup?

I own a small multifamily commercial in Albuquerque and can confirm the diversity of the economic and cultural factors that you mentioned. 

We measure against 15 different factors.

I've walked through a property with a wholesaler and when I walked in I told him the ceiling height here is a big factor for resale and I can't use the comps he sent me.

I have done some research, but I’ve found that many mentors and coaches are asking for significant fees, which feels like a large financial commitment, especially as a newcomer to real estate investing.

In your situation there is actually another factor that may work in your favor.Only the proceeds allocated to the sale of the building can be used in a 1031exchange. 

Not sure your situation financially but even your $100,000 HELOC is going to probably run you $12,000 additional each year in expense that you've got to factor in.

Fees are really low too. 

The biggest factor will be how long you plan to own the property or when you think you may refinance.