A suggestion:

I'm a photographer, and I require every model ... even if she's paying me for personal portfolio shots ... provide a photocopy of a driver's license.

No reason it wouldn't work online too. She can certainly mail a copy of her driver's license to you before you get into anything "interesting" if you have any doubt. Those who are of correct age will respect you for it.

And if she mails a fake or "borrowed" driver's license, you're still setting up a strong case for yourself and making it very hard for feds to allege "intent."


her_Joe