Avoid any ladies with URLs like the following:

http://(provider's name).hotlocalescorts.org
http://(provider's name).escortqueen.com/
http://www.speedsurf.to/(provider's name).com
http:// (provider's name).andrad.com/

The best way to tell if the agency or provider is part of this scam, is that they will have a set of pictures(which are links) at the bottom of the page with a header that says: "My best friends".

You'll notice if you click any, that all the same  girls are on all the sites.