I have absolutely no idea what you are talking about.  Who's on first?

at least 30%, to include added time for correct interpretation of what you want.

Hey Jasper18, my man, aren't you a little young to be out there hobbying?  In any case, assuming you mean a HJ, I personally don't do those.  And if I did, I would probably blow before 45 minutes and I'm a lot older than 18.  In fact if a provider 'rubbed' for 45-60 minutes, I would probably be a chafed, painful mess.
And why in the fuck would you pay anyone $160 for that?  I don't care if she were nude or the Pope's Rabbi's mother!

But somewhere in this dialogue I think we are in the back seat of a Chevy somewhere off the strip?

Re:How much to tip for R+T session?

Hi, Jasper...
  Now that you have clarified what R &T is, I personally don't know a lot of high level providers who even do those. Most providers that I am familiar with expect a 175-250/hour donation. If I client wants R/T for that price, hey, what the heck?
  I have to agree with some previous comments, in that, 45 minutes would be a heckuva long time for that type of activity, and I would wonder why someone who is 18 would even want that.
   Unfortunately, I can't tell you whether the prices are appropriate, because I don't play in that neighborhood. Since my sessions are 200/hr, it wouldn't be economical for me to charge the kind of prices you are quoting. If someone is charging you 160 for nude R/T, then that's a heckuva price. What do they charge for F/S? 600/hr?
  My clients expect, and recieve, the highest quality of experience they can obtain. I truly believe that in most cases, you get what you pay for.
   Good to talk with you, and thanks for posting the question!
     Hugs,
         Kat