Being a GC, Property Manager, and Investor myself, I can tell you first hand having the proper team in place is crucial.  

Anyone who owns apartments or understands everything involved could please message me to help me make sure I do everything properly, so I don't screw myself when investing in a potential apartment complex I'm looking at.

Proper notice should be given to the tenants already.

1) Give the proper notifications. .Keep the money. 2) No.

Some markets will have appreciation and may not cash flow day one, and some will not appreciate much if at all and cash flow great if managed properly.

Just be sure to operate them properly so as not to pierce your corporate veil. 

If you follow the BRRRR method properly, you can certainly accomplish this.

@James Colgan check out CBIZ or Proper.

I, on the other hand, feel I need a little bit more, like something in writing from that person that says they will not give the code to anyone and that if something is not left locked properly and the house is broken in because of that, then they would be held liable or something of the sort.I remember that there are people who do this, but I don't remember if there is a name or there is an example of said "addendum" for it. 

One has a partial flat roof and the other is all shingles (multilayer but less than 3) If the shingles are curling, bare or missing, just replace it properly.