Do beware of WGs. In my experience, you need to make things as clear as you can before things even begin. Also, you should be able to have a hold on them just in case they turn around and try to blackmail you in whatever means they can. There are a few pointers that I can offer (sorry if you already know them).
1. If you want the same girl for a few days for the GFE, try to tell her a longer period and then spring on her that you need to leave early due to whatever reasons that you can think of. Of course don't short change her. For example tell her its a 4 day deal for say... $10,000, then on the 3rd day, without any warning, just fake a phone call and tell her to leave (and you catch your flight out). This will avoid her from setting something up and holding you ransom to squeeze extra out of you.
2. If you can, take a different WG back and IF you really could, change room daily. If the WG is nasty, she can come back to your room and make a scene. (this is with experience)
3. Of course the WG is engaging in illicit activities, if you can, get some 'evidence' be it in terms of audio or pictures. Just in case... u may share with us also...
4. Never pay everything upfront. I normally will not even take all my cash and cards out of the hotel. Just in case you get scammed and they want you to swipe multiple cards to 'pay the bill'. At least with one card, once you limit out, they'll have a tougher time getting more from you.
I had my nasty experiences and these are paid in money and ego. There are professional WGs and there are ones who are nasty with thugs to back them. I must say that you do plan ahead! A visit next year and you're already preparing for it!