You gain little and add complexity and redtape / limitations.

I did a curb appeal mockup for you (but I think it's more than curb appeal), If you have for instance a proper class C apartment complex competing with you, the layout will be more home-like vs. this house cut into two parts with less than desirable floor plans.People don't pay Cadillac prices for a Pinto, but a fixed up Pinto will bring more than one with dents in it.On the plus side, it's clean, the neighborhood looks great, I like the backyard as a feature, I like the garage as a feature, I like the "STORM Cellar" as a feature re Tornadoes which apartments do not have, and it looks like at least one unit is ready for washer and dryer inside the unit, which apartments sometimes do not have.You may have to do more to the interior to close renters on the place if you can't do it as is (spend $$$).Here's a curb appeal mockup, I just chose a paint color at random, but white might work better in the neighborhood.I doubt just curb appeal will make it the most desirable rental in the area though, but it's some food for thought.I like this house, it has potential.Right click open in a new tab makes it bigger. 

I was able to save money by collecting rent from my friend rather than have to pay rent to an apartment complex.

I personally LOVE Syndications because of the experts I get to invest alongside while THEY do all the heavy lifting.However, direct ownership of rental property can be a boon, too, and is not nearly as complex as you may think. 

Its not too complex, but not trivial, either.

Much more complex and operationally intensive than other real estate plays.

HAFA is complex with many rules and guidlines.

LOLSee if you can find a real commercial brokerage as Joel suggested.If you want classroom study, see what you can find at a local college or university on the subject and stay away from gurus.And, guess that also means what you call "commercial" a 6 plex or a shopping mall, maybe an industrial complex on 20 acres?

Unless each of your properties is a 100 unit apartment complex, there is no need for that many entities.

Let me try to give examples.If you try to set up an entity to build a 500 unit apartment complex.