Hello Ladies and gentlemen,
I'm planning a trip to Vegas, I'll be there for 5 days. My question is what would  be good time frame to book for? I don't have much experience at this and don't want to book her time and not be able to rise to the occasion.  
Thank you

If it's a girl I've seen before and like, I usually book 90 min to two hours.  But two hours can feel like an eternity with a girl you don't click with in person.  So I've found 60-90 min is good for a first time session.  Although I have been known to book a 90-minute starter session and extend it to two hours if it goes well.  If you do that, you have to remember to have enough extra cash on hand and you also have to accept the risk that she might not be able to extend due to other commitments.  Good luck!!

I have had gents I met for the first time book an hour and others book a dinner date.
It depends are you a guy who likes to talk a little before having fun or grabbing a drink first?If so perhaps maybe 90min or 2hrs.You could also just book an hour and then if you want to extend time just ask her if that is an option if an hour is not enough.
Have fun in vegas we have so many things and ladies to do out here

...rather than having a possible session from hell and you booked for 2 (or more) hrs.

s others have alluded, there is nothing worse than paying for multiple hours with someone whom after five minutes you have no interest in being with. For new hobbyists, I would recommend an hour for a first time visit. This should be enough time to gage whether there is chemistry between you two and whether she is someone you'd like to see again. Yes,  I have done several first time dinner dates (4 plus hour appointments), but I was fairly confident based on the ladies review history and my own instincts that we would be compatible. I have been fortunate to date to have had really good experiences.  But most of my first time appointments are an hour.  

8 to 9 inches, on a good day

then a gal told me that an hour was fine & we'd finish what we started...  been 60 since then.