the first thing is overall looks and appearance. Then it comes down to how she describes/portrays herself to determine if I think there would be a connection. You can have the most gorgeous woman with the most amazing skills, but if there's no connection it would be a disappointment.

her reviews scores, especially for performance.

Also number of reviews.

Within a certain range of affordability, that is the key factor.

I also consider how well done her website is, and also if she participates on the boards, how well she presents herself on there.

Recommendations from people I know and trust also plays a factor.

For lack of a better term, it's her personality (yeah, go ahead, laugh your asses off).  I've met many providers with absolutely perfect breasts and/or butts.  Age really isn't a big factor, although I'm older, uh, more mature so I prefer more mature providers.  As for menu, I don't have any problem finding providers with an agreeable menu.  Price isn't an issue, either--plenty of great providers with reasonable prices where I live.  Beauty is subjective.  For example, I think my atf is gorgeous, an 8 on a bad day and most days a 9, but some have rated her as low as 6.  

Personality is what influences me to see a provider again, more than any other factor.  And wrapped into that word are many attributes:  intelligence, confidence, playfulness, sense of humor, kindness, inventiveness, and grace... and a few others.  My atf crosses the bar there more than any other provider I've met.  Which is why she's my atf, and probably always will be until one of us retires.

Her Reviews. If her reviews are great, then I'll go see her. If the reviews are not so great or bad, then I'll keep looking. Looks don't attract me like it used to when I was younger. Performance is a key factor with me.

But that can be hard to determine before meeting. So it goes to looks and reputation. On the looks front I am a face man but as that is often cropped or blurred breasts that are mid size (B or C) and natural are the next big draw.

no up-selling or premiums whether noted in "Cost of Service" or not.

Then photos/appearance

I'll admit that I read between the lines to see if she's a cool person.

I do love a great ass, and legs, so that can often be the final deciding factor.

But when I'm choosing a lady it's her menu and performance to it that propels me to investigate further.

Location and Price open the door to further research.

Size, looks and activities all play a roll.  

All "standards" may be reduced depending on desire/need

I like:

- Facial photos – right there on her website (without any "private viewing" arrangement)

- Photos of her in party outfits, revealing a nice ass and a trim belt line  

- Good grammar and succinct expression on her website pages

- A slightly premium price (it says a lot about quality)

How a woman looks in a tight dress means more to me than how she looks in her undies. Frankly, on provider websites lingerie shots are vastly overdone.

What attracts me

Several things.  
Age- nothing younger than about 30. At my age I  require a more mature lady.
Her menu of services must include bbbj, cim
Price somewhat but that is variable.
I prefer petite but with curves, no spinners.  
What brings me back for more is personality, intelligence and the above.

Hands down, continuous interaction.  That assumes mutual attraction, enthusiasm, spontaneity, imagination, and an ability to stay deeply attached during the entirety of the event, whether it's an hour or several.  For me those occasions are not to be taken for granted; you can't ensure that they will always occur, but when they do grab them and enjoy until exhaustion.

guys state for booking me. They probably do not even think I am all that hot, but like my personality. Well ok, not the mangina crowd, but the real men who like a bitch with some spunk and actual credentials.  If all you want is an acrobatic monkey, you can have one for a lot less. I have actually had guys say "I was scared of you" lol, but still booked. Yah, I took THEM to dinner ha ha.

1)  Price: self-explanatory
2)  Body type: the slimmer the better
3)  Menu: more GFE is better
4)  Geographic: local girl is better than visiting talent

Yes in that order

I've been in the hobby as a client for 11 months now and have put in a lot of homework to determine what works best for me.  There really are two categories:  1) meeting a new provider and 2) continuing with a regular.

in category #1 it is a mix of physical attributes and personality (based on their ad photos, self description, and reviews). I like petite. small to medium breasts (natural), laid back and personable GFE.  

in category #2 to keep me coming back , we need some chemistry, and she has to be reliable for booking. The regulars I prefer all have intelligence, can carry on a conversation, good kissers, get into the session and like to make out a bit. They also all have a sense of humor. I prefer t book in advance of at least a day or two. Sometimes a week out.  There are a couple of women that I see who work best when I contact them the same day, instead of a week in advance.  I visit them less frequently. I understand the ladies are working a calendar and cancellations happen a lot.

This answer is running too long, I think you've inspired my next post.

Establishing a good rapport with them at an M&G, or hobby related swing parties.  Physical attractiveness counts as well, but since most providers are attractive, this isn't an overriding concern.