@Jonathan Twombly brings up all very good points and lessons first time MF investors don't realize and learn after trial by fire!
@Terrill Clark when you say "actually net" are you referring to rent increases? In that case, it will wildly depend on your comps in the area and how much you put in for rehab and interior upgrades. There isn't a one answer fit all unfortunately for that question.
Seems like you're a hard worker and willing to put in the time. Is there a reason why you want to go it alone? My suggestion is that you first become a passive investor in a MF syndication.
What this will allow you to do is get access to the inner workings of how to structure a deal and give you a direct line to a sponsor. This will however typically require you to have 50k (typical minimum investment) and be an accredited investor / sophisticated investor depend on the sponsor's investor requirements.
Something else to consider is unless you plan on self managing, going straight into 60+ unit apartments allow you to be able to carry the expense of a 3rd party management company. Typically anything less won't work as the margins aren't there for them.