You generally don't offer them money. You talk about what they need and what things they like and it just evolves. If she has GPS, that will soon be apparent and you move on. If she's reasonable and within your budget, you proceed.
Originally Posted by John Bull
+1000 to you John. I've recently taken the role of SD and so far I'm really enjoying it. In total (money, gifts, favors) I probably give a little more if averaged on a per hour basis but it's much more mutually beneficial. More like a good "friends with benefits" relationship. So far, she hasn't developed GPS, has traveled with me a couple of times and seems genuinely appreciative when I do her a favor. The SD/SB relationship must be completely different than the "escort on retainer" deal, otherwise it will die quickly. Most of us aren't looking for a strictly business deal, otherwise that's what we would pursue.
Good luck in your search. It takes time and patience but if you approach it correctly, you will find what you're looking for.