I'm also in a position to cover any capital expenditures for the foreseeable future, which would most likely be the HVAC, since the roof is 6 years old.I'm also carrying a mortgage on my current residence for $800/mo. if that would factor into anything.I'm self managing the property, to get some experience and saving on PM fees. 

That's 2.6% gross return before taking off all expenditures.

Oh, one other question re capital expenditures: how do you calculate for those?

Because a four plex is a rental...always a rental, you may find a good many as I did...in rough shape, needed a lot of capital expenditure (CapEx) once you acquire the building, even if the price is good.  

Often it includes all costs and expenditures to date or somewhere between the two which makes it not worth bidding.

The second expense you should factor into your analysis is Capital Expenditures also know as Cap Ex.

However to be honest, these are just rough estimates and you really don't know with any precision the capital expenditures that will accrue once you first take possession of the property. 

I'm currently netting about 9% on them (income only and not including price appreciation), but I had the advantage of purchasing them a couple years ago in Tampa, which was good timing in an excellent market (and also had a good year last year with very few capital expenditures and repairs.

We commonly find that between deferred maintenance and capital expenditures, the investor spends much more in the initial stages than they had planned. 

Finally, you should have cash reserves for capital expenditures (CAPEX).