You need to know the quality of material you're going to put in and how much it is going to cost, then just plug the numbers. 2) People are doing the deals to squeeze as much out as they can with minimal investment.

I'm going to throw out some additional considerations.Your advantage right now is your age and the ability to finance (at historic low rates) a 4 plex as a personal residence, with minimal amount down and use the income from the other 3 units to help qualify for the loan. 

I know turnover is part of the business but I know Mack minimizes the time and cost.

This gives you a guarantee of a minimal rental increase should the CPI calculation be low, something you can't control but with this method you have a "worst-case" floor minimum rate increase you can depend upon. c) If the Tenant objects to the "minimum floor rate", offer to counter with the addition of a maximum "ceiling rate" that the Tenant could be obligated to pay.

We have a clause in our lease that allows us to show the rental after the tenant has given notice to vacate.My goal would be to minimize the vacancy time.

Interest rate minimally higher.  

Low maintenance plantings, especially foundation planting, artful use of gravel, and large mulched beds.Low maintenance plantings, to me, are those that require minimal or no trimming.  

@Mike McKinzieI realize that there are other investments out there that probably have a higher ROI but considering it is cash flowing now, I have minimal out of pocket cash and room to grow rents to about $8,000 per month within 12 months.

With managing mult-family apartment complex of 260 units we do try to minimize the use of the court.

Co-app 1 has 800 credit score...no outstanding debts other than minimal credit card debt.