Vanessa of numberoneescort.com is a classic 'send-me-the-money' rip-off.  There are several of these scams present on the internet, and most of the ads are similarly constructed.

A deposit is required to set an appointment; once sent, no additional contact is ever received. With no email or phone number listed on the web site,  no reviews can be submitted to TER about the experience.

Check the link below for additional information.

- Gadget

As Gadget wrote, you have no way of contacting the person other than the form. You also have no way of getting your money back, if that was possible to start. For all you know a massive burly man can be behind the site and is paying a hot model money to pose. Take your money and RUN, not walk, to a legitimate provider. Ads like the one that you found is why all of us come to this site.