I've hired twice at the Stratosphere. One time I went down at met the provider, the second time he (a different guy) came up to my room.
Third hire in Vegas was at a humble Red Roof Inn (on Flamingo I think??), which had outdoor room entries so he came and knock-knock-knocked.
No problems, no security in any of those cases.
HOWEVER, that was a number of years ago. Maybe things have changed, which is why I kinda freak a bit from the Vegas law enforcement risks outlined in another thread.
So I'm curious about the security question, too. Nothing beats Vegas as a place for some MUSCLE to garnish a fun trip.