This is my main thing! I have a whole series of blogs about travel/FMTY etc.
As for how to choose the right person-
-Chemistry is obviously most important, in and out of the bedroom. Look for someone with personalities and hobbies in her ad, not just physical focused. She should be interested in what you're interested in for your trip! Want an outdoorsy trip? Find someone who's into that! Museums? Great! Vegas party? Etc! Scroll through her twitter and website along with ad to see what type of dates she enjoys.
-Make sure to discuss alone time and down time along with sleep- 8 hours of undisturbed sleep is definitely a requirement! Talk ahead of time around what both of your bedtime habits usually are. If you're aware you snore, it'd be curteous to get a separate room but definitely isn't required. As for alone time, usually if it's 2+ days most people require a couple hours of alone time per day to not get stir crazy. There's things they need to check in on and time to recharge! Even if you're with your best of friends or family, alone time is still wanted, so especially here. You want her at her best!
-Travel- If flights are involved, plan on travelling separately and meeting there. For discretion purposes of course, but also because travel can be tiring, and people want to be comfy cozy, sleeping and relaxing on planes and able to relax rather than worrying about having to be their best.
-Rates: Some people, like me, have flat-rate trips where it's an all inclusive price of her time, the travel fees, etc. Some people do custom depending on when you go, where, activities, etc. Check her website and ads ahead of time to see which is which!
And of course, make sure she's got her passport! Since you're travelling separately global entry isn't as much of a requirement (but I'd definitely recommend it for her so she's not stuck waiting in long lines :P
Happy to answer any other questions! I do a lot of trips with clients whether it's joining them on a business trip to make it more enjoyable or checking off bucket lists! Recently with gents I've taken on Japan, Spain, the Netherlands, Zion, Costa Rica, Dominican Republic, Boston and more! In my own time this year I visited Antarctica, and am soon heading to Southeast Asia!