Let me take the first stab at this...
In Michigan, you need a Purchase Permit, available from your local PD, in order to buy a handgun. If you have a CPL, you do not need a Purchase Permit. The federal 4473 is also required.
Once you purchase your handgun, you need to take it and the Purchase Permit, or the form you filled out because you have a CPL, to your PD for a "Safety Inspection." At that time, you will receive your "Safety Inspection" card that you are supposed to keep until you get rid of that handgun. Yes, the state does keep track of these "Safety Inspections".
You only need the Federal 4473 for long guns. No "Safety Inspections."
I'm pretty new to AR's, so I don't know any specifics there. I do know that we have some sort of length requirement... There's a recent thread here about that.
Others will have more and maybe better information... but I hope this helps.