How to know a duplex is a good deal?

[Daniel Okon]

I am starting looking at duplexes and I am just not finding very good value especially because I am planning on doing the FHA 3.5% down and live there for a year starting out. I have found many duplexes that are around the 220,000-275,000 range that are only charging rent at the rate of 950-1250 per month on one side. I really was hoping to find a property that could essentially take care of the mortgage costs plus maybe a bit of the utility costs as well as some taxes as well. Is this a little too optimistic? In reality I've only been looking for the past couple weeks but is this something I should be looking off of mls? Any advice is recommended. I am out of the Minneapolis/St. Paul in Minnesota.