The income will probably not be sufficient to live on so I would recommend you pick up another full-time job.  

In addition, the owner of the home must not own more than three single-family homes.They are unable to provide sufficient documentation, such as the emotional support animal letter, that verifies the ESA is necessary for their health and well-being.

If you are going to use an FHA loan, it will be important to remember the rules of FHA's Self-Sufficiency Test (SST).

.-  Your unit revenue and quantity has to be sufficient to offset the "costs" your putting in. 

Not to mention, FHA has a self-sufficiency test you must pass on a 3-4 unit. 

Maybe even consider FHA if multifamily is the route for you with 3.5% but you will need to past the self sufficient test if you are acquiring a triplex/quadplex.

If I were planning to consult with a tax adviser and attorney to work through this process, I assume that would be sufficient to mitigate the risk. 

FHA has an added guideline on 3 and 4 units called self-sustainability or self-sufficiency (i always mix them up). basically it means that the rental income from the units have to fully sustain the PITIMI, or else its a no-go.

I don’t coach in those things because I don’t feel my experience is sufficient in those area yet.

People who live in high-crime locations and have sufficient income will leave.