One of the big HOA managers in town retired a few years back and left his kids to run it, the downfall has been noticeable in communities they run (which is many of them). so do extensive due diligence.

Keep in mind your holding costs also will include utilities and insurance (I assume you plan to carry insurance). 

Residents pay all utilities.

(After accounting for other expenses: utilities, appliance, extremes I am looking at a total of about $1,020/ Mo.).

not reallyAnother level of complexion is losses that are passive may not be utilized to offset your other income while some taxpayers can. sometimes it's best to keep things simple. 

Generally, if there isn't a separate meter, landlord can't make tenant pay utilities as there is no way to truly decider what portion of the bill belongs to which tenant.

Besides the obvious costs like utilities, insurance, maintenance, and taxes, are there other ones I need to know about and what they would run?

The low money down and the ability to utilize a 203 B or K, that program is pretty nice. 

That is before other necessary costs such as utilities & water and other basics that are not necessary but often included anyway like phone, internet and cable. 

Recent price reduction of $120K and we got it under contract almost immediately after it was listed at the new lower price.We have done local rent surveys and we think we are competitive.We're still in the Due Diligence phase right now, and are getting: Appraisal, environmental study, HUD statement, utility details, insurance, financing.Anything that you think we should be considering here, either about this deal or about getting into an office building in general?