Negative ROI!?! Are my calculations off???

[Spencer Gracia]

Hey Guys I am a rookie investor (Still have not purchased my first investment property.) I have had some issues calculating ROIs. I am in the Los Angeles area however I have been looking into investing in the Memphis area.These SFDs seem super affordable (150k) and under but it seems like when I find a home on the market the ROI calculations always end up upside down, becoming negative. My question is, am I simply looking in the wrong market? Or is there something im not looking into as far as having positive cash flow. I hope Im making sense in my questions.

Thank You in Advance!