AIV is a company which has bought apts at the top of the market. Boston where I live they paid 120k per unit versus going price of 90k per unit. The market than tanked. They then bot NYC commercial prop at top and they don't know first thing about that market. They took to long to cut their dividend. I could go on and on.
I bot maa as an owner of apts myself because they have kept them up better than most and they are conservatively run.
These two should not even be compared but aiv may become a buy around 30.
I think AIV's problems are mostly generic to the apartment industry, generally. They own far more units in more locations than MAA and conditions in certain markets may have hurt them more than smaller REITS. Higher vacancy rates due to big increases in home ownership, and a sluggish economy are troubling everybody in this business. Three cheers to MAA for doing a great job in difficult times.
AIV's problems are generic, in part, but also the direct result of greater leverage and less focused (and less shareholder-friendly) management.
I've had some run-ins with their CEO in the past(I was the lead plantiff in a (winning) class-action against him a few years ago, in fact) - Let's just say I wouldn't touch his stock if it yielded three times as much as MAAs.