Originally Posted by Cat Herder:
Most of my rules are because someone once did "something stupid" 
Liability:
1. Once my neighbors cat sprayed it and the Mom felt I should replace it. I never gave her permission to leave it and did not know it was outside. 
2. One Mother was in a wreck, minor fender bender, and was cited for not having an infant restrained. Baby was bucked into seat, but not car.She blamed it on the fact that she was in such a hurry to get out of my driveway for other parents since I "WONT stagger pick-ups". (my closing time is 6, so everyone waits until then, and this is my fault how?)
Space:
1. My Foyer is only 35 sq feet, my front deck is open to neighbor dogs/cats, and I am not a storage company.
Odor:
1. Ever had that 5 day old dried Urine/Diarrhea smell in your living room?
Filth:
1. Ever had someone Else's month old French fries, goldfish, cheerios, cigarette butts or something I pray was smooshed up fig newtons all over your entranceway?
I just chalk it up to Parent Responsibility. I knew when I had kids there may be an emergency situation where I may need someone to get my kids. DH, my Mom and I all had carseats in our vehicles at all times. I was invested in my children.....before they were born.
You forgot hitch hiking bugs... like roaches & lice, bedbugs & GERMS. Yep, I actually have this listed in my policies along with the above. Never had a parent complain. You never know where the parents have hauled that seat too ( Hotels, Gyms, Dr's office?)I personally don't have room for carseats in my home or on the deck we play on so that is the main reason, but I also state liability issues