How to "make money when you purchase a place"

[Joe B.]

Hey guys, been doing lots of reading, listening to podcasts on how when you first buy a property, you should be making money. What exactly does that mean? Should the property have renters in place already? My plan is to use a FHA to buy a duplex as my first property. If not use a fha to buy a sfh. How likely is it that property does have renters in place? Is it a crapshoot?