Largely due to the low quality tenants these homes attract due to their geographic locations and being in a very tenant friendly state/city.Now due to their very low cost basis, the trust would be on the hook for massive capital gains taxes if they were sold. 

In my market, duplexes sell at a marked discount to single family homes (for comparable size and finish quality, can be 30-40% depending on submarket).  

Consumers don't want to pay for quality, manufacturers cut corners because they are more concerned about profits. 

When you are truly dedicated to the building you are buying, you would want each of the units to have the best quality of interior and exterior.

There are portfolio lenders who look more at the quality of investment you're looking to buy and may potentially allow for a lower down payment.Another good option if you're current life situation permits, is to do a live-in flip, or make your new property your primary residence.

There are a lot of great investors here in Baltimore, especially on BP, so don't hesitate to ask questions as you get up to speed.

It's all about quality v quantity, right? 

Buy a 2-4 unit (or SFD and house hack) in a quality area, within driving distance to you job.

Anyone can wholesale as you know, but what makes a good wholesaler in my opinion is the quality of the numbers and data they supply. 

Also, make sure you find quality tenants who will maintain and keep up with the property.