Assessing A Properties Value for a Rental - Cash buy or Mortgage

[Michael P.]

I am currently on the hunt for a rental to purchase.  I have lets say 45 cash. I also have excellent credit, a FTJ, should I go after a mortgage?

I have a property, ok area, zillow assessing at 75k, owner is old, looking to sell at SFH, 45k, with tenant paying 800 a month. If I buy it cash, i am cash flow positive day 1. 4 years its paid off.

So this is now a 2 part question.  How to assess if its a good deal, and should I pay cash, or get a mortgage.