Where are the best locations for multifamily investments?

[Coco Cook]

I have several articles describing best and worst locations for RE investments. One article mentioned SF and LA so I threw that one out. I've read Denver, Charlotte, Phoenix. Some factors to consider are population and job growth, economic diversity, how landlord friendly the market is, etc. I'm looking at four plexes. Anyone with experience in any locations they think are particularly good and can explain why? Thanks. 

PS-anyone looking at Detroit?