It is not a scam in every situation. There are quality providers with great reps and a huge online presence, such as myself that do legitimate prepay specials.

I get dozens of emails a week from clients in different cities asking me to visit. If it is a new city, it can be a huge financial gamble. I will offer a prepay special offering free time for money in advance. If I get a couple, I purchase my hotel and airfare and go. Anything else I make is profit. The guys doing the deals get a bonus and they help me. It is not a scam. It is genius marketing. Lol.  

Yes...there are scammers
 Do your research. Girls with thousands of twitter followers and 50-100 reviews most likely won't scam you!

There is a pretty well known lady in Philly who I follow on social media. She posts all the content she sells multiple times a day and lists numerous cities she "visits". Was in touch with her in Jan and she said Minneapolis was one of the cities on her "list" to visit. It was like 200-250 to prebook a date with her in hopes she actually shows up. After some research there are alot of reviews of guys funneling her money in hopes to have her come to their city but she never showed up - oh well, Let's just say I did not prebook.

Unfortunately during my first few inexperienced days I had sent pre-book money to DaniDD. Didn't hear from her for six months after deposit.