At the very least, plug her phone # back into the search function and see what other ads or replies come up. Do a reverse directory search on the #, too. I wouldn't go anywhere for incall except a hotel without the room doors exposed to view in the parking lot. I'd also take a drive around your local police dept parking lot at about 8:00 AM when most of the undercover cars are there and see what they use so you can look out for them. I'd also let a trusted friend know what you're doing and the room # and tell him you'll call him when you're done. If you get there and it feels wrong leave. May sound paranoid but none of it will hurt you.