I really would want to stay away from any office properties in depressed or even semi-depressed neighborhoods, especially large ones (like a 13 unit complex).

Most of the time, we resolve the situation in less than three months through cash-for-keys agreements, court mediation, or by creating enough pressure that the tenants decide to leave on thier own.We currently manage over 700+ units and flip about 20 multifamily properties a year, the majority of which have inherited tenant problems.

Built in 1905, this property features a total of 2,832 square feet of living space, divided into two units.

Aside from what everyone else wrote, note that adding units require various steps that you may not have considered (e.g., adding a new street address with USPS, etc.).

If you really want to get rid of them, sweeten the pot by offering to return their deposit after you verify the unit is empty with no damages. 

Once you take over a property as an owner occupant, if it is a single family or condo you can live in it for 1 year and that automatically exempts your unit from rent control.

You should consider getting the most units (that can rent for the highest) for the best price.

Assuming you currently rent right now, and you are buying the single SFR as a primary, the 3-unit should just be designated as investment and you should be able to use the rents to offset the payment (up to basically 'zero-ing' it out, on paper). 

@Albert Gallucci as many have pointed out, in the commercial space of 100+ apartment buildings and offices, property classes have some pretty decent industry standards.We started applying these to 1-4 unit properties around 10 years ago, which you can verify on our blogs, because we saw too many newbie investors not properly taking into account things like, neighborhood status, tenant pool, property condition, etc.Unfortunately, there's no industry standard for this, but you can use some basic logic to think your way through your own Classifications.

Try to get as many units in the building as you can.To Your Success!