Security guard is a very good idea.
Re: Keying
-If its kids; that very sad. The reason is 100% the parents, period, full stop. Parents set the example, and kids follow: ie, trashing a hotel room, beating on a rental car, slaming your door into another car, road/air/food rage, etc. Unless you drive home respect for yourself, others, their property, its all a waste.
I am not pontificating either; had 2 tires slashed (Michelin XVX $450 ea.) and one side keyed on my BMW in Scarsdale, NY (Beverly Hills of NY). I am 100% sure it was a native of the community; not a working class kid from neighboring towns (generally have better moral/work ethics).
I felt sorry. Some kid either had parents, peers or such low self esteem that this act is the best he could come up. A long life of failures/mistakes is ahead of this fellow and his parents. Michellin popped on two new ones and prince of a teenager with his own detailing business spent 6 hours (@$200+ 50 tip) on that same car, and made it look new.
Old saying where i come from: "Dont lend your sword (gun), camel (Horse, GT), or wife to anyone; might not like it when you get it back"