The quickest way for a provider to lose her looks is to do the unmentionables. There is no such thing as the occasional sniff or iv hit. This also includes prescription abuse.
Alcohol is tricky. The occasional or even daily alcohol use i guess is ok but to get drunk on a daily basis is another quick way to lose your looks.
It's just bad business to come stoned or drunk to a session be it hobby or civie
Btw this goes for hobbiest as well.
Carry on people