Buy a place to live and you have the opportunity to gain equity that way with a really low downpayment if you go FHA.

It's a dry heat here. :)

I have great loan guy in the Columbus market that does nationwide loans and can do loans for homes low as $20,000 sales price and doesn't add junk fee's or hike up the rates because it's a low sales price.  

That seems way too low.

In order to subdivide this lot, I would have to convince the city to change their zoning map and allow for a smaller single family lot size than what they currently allow (very low odds this would be approved).  

As a retirement plan, the Solo 401(k) is vastly superior, with significantly higher contribution capacity, the ability to make Roth contributions of up to $18K per year with no income limitations, etc.Depending on your ability to contribute, and therefore how quickly you can amass some working capital, you may choose to start with a fully self-directed Solo 401(k) or you may choose to establish a low-cost brokerage Solo 401(k) that would be limited to investing in stocks, funds, etc. for the near term.  

I'm looking into buying the first investment property, and it seems like the only thing I can afford at the moment is properties from a low-income neighborhood without putting me into significant financial risk. 

To start - need to research deep and a lot of due diligence.High price will put you out of market, low price attract low quality tenants.

Unless you are buying some really low end commercial property where $800 is significant... but in that scenario I probably wouldn't do the deal anyway. 

Looks good, low maintenance.