I am unaware of any law preventing a mezuzah at the entraqnce of any home. I put one on the door frame of my last house, and my front doors are always red. I also have a fish on my Infiniti. Praise God!
Homeowners associations do it.
I’ve seen a retirement home that forbid them on the units.
Just covering all your bases there paperdoll?
I did just last week paint my front door red.
Trying to send a message to some of the evil neighbors.