Ohhh exciting!! Out of curiosity, and you dont have to tell us, but how much is he paying and id he paying for flights etc too? I have had a similar offer and dont know how much to charge!
I wont say what he is paying but it is a lot more than two 30 minute bookings
Yes he is paying for flights and hotel.
Charge what you want, I mean think about how many days you will be away (including travel and a day or two to recover from jetlag) how much would you isually make in that time at home? Remember it's not worth it if your going to be earning less than you usually do.
Also is he paying for any entertainment, or your food and drink, how many hours of sex etc does he expect, will you have time to yourself?
These are all things to take into account when figuring out what to charge.
And just for any newbies: My situation is very rare, 95% of enquiries like this are from fantasists.