How should I compare/evaluate an existing apt complex (not my own) vs a condo I'm trying to rent?  

Listsource.com or any other list provider can get this information.Go to listsource.com, create a free account, then call their customer help line and they can walk you through exactly how to do it.This is a list you'll need to BUY.Free way is to search county tax records through MLS (see if you know a Realtor who will let you borrow their ID) or at the county court house for properties owned a long time- i.e. 20,25 years plus.  

Check housing court if you can to see if tenants have ever been evicted anywhere else.

I can't seem to find any info on the County Clerk of Courts web site.Thanks!

My goal is to own a mobile home park or apartment complex in the near future and to never look back on working for someone else!

This is a very complex subject and an unpopular one for some so I won't go any further other than to say that you can't just look at a neighborhood in isolation. 

The last apartment complex I lived in had stained floors on both upstairs and downstairs units.

Not sure what exactly you are looking for but in virginia beach I worked as a project analyst for apartment complex!

I've always been very good at putting together complex, creative deals both in real estate and other industries. 

His point is the complexity will provide protection.