What to look for when touring a multi-family apt complex

[Tony Castronovo]

Just starting to venture into the multi-family arena. I have solid experience on the SFR front but trying to understand what to expect when I tour my first apartment complex. I understand the financial analysis side. But what should I be looking for when touring a property? Will I be viewing a model...or various units (certainly not every unit)? Do you try to inspect roof, mechanicals during the first visit....or wait until the due diligence period?

Also, I know everything is negotiable, but what is a standard commercial real estate broker commission?  I know typical on the residential side is 3% for each side.  Is commercial typically higher?