Again, when I confronted management, they didn't tell me that they had knowledge of the tenants living with many others and the tenants violate several codes.  

Once you confront the owner, it will not be pretty.   

I don't want to risk confronting him and he loses it and trashes the apartment or something.

could anyone shed some light on finding and structuring whole sale deals, just trying to get my foot in the door on confronting owners of multifamily ?

This particular case happens to be in Florida.NOTE: do not be like this Landlord and confront the squatters unless you are prepared to defend yourself.

When I confronted the Section 8 caseworker he told me there was nothing he could do about it.

The sheriff will post a notice of their own on the entrances to the premises, then will enter the unit to make sure it is clear or to confront the tenant, and then once the tenant is out, they will stand by as you change the locks and empty out the dwelling.This is not legal advice.

No need to be confrontational, just politely state the temperature will be set at X, if you prefer it warmer,  it is permitted to use portable heaters. 

Being a landlord means being confrontational sometimes .

I will let him know that there is nothing I can do and he needs to contact the police department (which he now does whenever a confrontation happens).