Comparing Rents for Duplex/Triplex/Quad versus SFH versus Apt

Hey Everyone!

I am looking to continue studying the rents in my area (right now Chandler, AZ) to make sure I am ready to jump on the next deal when I see it. However, I frequently run into a challenge where there seems to be a pretty big disparity between what a 2 bedroom apartment will go for versus a SFH versus even a duplex etc.

Is there an industry or area rule about how one type of property will rent per square foot compared to another? If not a standard, what are things to keep in mind that can help me gain the most accurate number when deciding on what a particular property would rent for?

Thanks in advanced!