How to best choose a Property Manager?

[Erik Gensler]

Hi, everyone. This question is for the landlords out there.

I am a total newbie to real estate investment and I was wondering if anyone had any recommendations for how to choose a property manager.  I will be the landlord of a 28 unit multi-family apartment complex.  

What is the most important quality (or qualities) you look for when choosing a property manager?  What are the common pitfalls you look for when hiring them?  What are your biggest frustrations with them?

I have some ideas myself, but would be interested to hear what more experienced landlords have to say.  Any advice helps.

Thanks in advance!