try to explain.
The larger cities (NYC, Chicago, LA, Miami, etc.) will generally have higher rates partly because the lady's overhead (maintaining an incall for example) is higher. Supply and demand may help keep the rates in check somewhat since there are way more providers in any of these cities than say St. Louis.
The providers that provide the ultimate GFE experience and continually get the high review scores and glowing reviews will generally charge more than the new girl just starting out or the experience lady who doesn't always bring her A-game. You need VIP to read the reviews; don't just go by the profile page.
Find a lady within your budget and enjoy. Life is too short to say "I wish I had done this sooner".
Unless the lady is really inexpensive, you have to go by the reviews to know if she upsells. Some nice ladies are reasonable to get more business. Some not so good ladies set average rates, and still upsell (CBJ is included, BBJ is extra). Some ladies set high rates, and things are not on the menu.
Note: If she tells you in advance, it is not upselling. For instance, many ladies that offer Greek (PSE is often a code for greek) will have a rate for that (and you should tell them in advance if that is what you want).
Stay with well reviewed reliable ladies, and you should not have to worry about upselling.
Paid between $160 (AMP, sort of) and $400 per hour both for single hours and more extended visits and never once was I asked for more money. On a couple of occasions ladies turned down extra money (no, I do not believe this is because I am a special guy, just what they do). So I think you are very, very unlikely to be upsold if you stick with well-reviewed ladies and are not looking for a quickie.
As for a norm, I could offer some rules of thumb like others, but there are going to be as many exceptions to any rules, including those already mentioned, as there are ladies who follow them. Geography? I live in Chicago and it is mostly more expensive than other, smaller cities so a lot of traveling providers are bargains, but I just spent a lot of money on a lady with minimal reviews from a small town (twice I did this in ten days) and it was wonderful. Quality, services offered, track record? If someone has found a consistent pattern between these things and pricing, please post it. Mostly what I see is that people post what they believe the relationship should be, but observation says they are wrong more often than not.
My rule of thumb is that you pay extra for smart women who understand a little about business and marketing (because they figure out how to fill up their dance card at the highest rate the market will bear), and even more for truly beautiful and classy women who can be eye candy you would gladly take anywhere because a lot of guys seem to party with their eyes, and the look in other guys' eyes, and the most for women who are smart and beautiful eye candy. I think there also is an upcharge for statuesque blonds with perfect breasts, tho no one will 'fess up.
But those rules are wrong as often as... oops, repeating myself.
Pretty much anywhere in the US you should be able to find a wonderful woman who will take care of you in every sense for between $250 and $350, and if she has 5-6 good, recent reviews from hobbyists with decent track records of their own (6 -10 reviews in the last 6 months to a year) , she will not try to upsell you.
But let me put that into perspective - the connection and the fun are the things. Paying $400 is a bargain if you have the time of your life, while paying $200 is a bad deal if you leave asking yourself why you did this. And beware of being influenced by glossy, fashion photos as they make it very hard to know what the woman really looks like.
Anyway, don't worry about saving $50, worry about having a wonderful, safe, time and pay what you need to pay to find that.
Hope that helps. Have fun,
Zig
