2 and 4

Scan all the review summaries.  Read enough reviews to get a consistant picture.  If too much YMMV I just move on.

Look at pics

Look at reviews  

Decide if this is what I am in the mood for

3,4, and read her reviews.  
If some of the reviewers are those whose judgement I value, I follow up...there were previous posts about the quality of reviews.  Like Olympic figure skating and diving, I drop the high and low outliers and read the rest.

First thing is check her price range.  Delete any hh ladies.  Price range needs to be in my sweet spot.  My experience is you typically get what you pay for.
Read her P411 bio and look at pics there and website.  If all fits what I'm looking for I will look at reviews, mostly from the perspective of how many and ratings.  If they are high and have no reason to believe they are fake, I will request an appointment.  Has usually worked well for me.  With all that said and done the one thing that holds true in business and in life is YMMV.  It applies here for sure.

so 1 and 2 are out.

I don't rule out the last, but have not done so as yet.

 
I often become aware of someone I want to see as a result of her board postings, and I always visit her website.

 
The most important research is her reviews of course.

 
Another avenue not mentioned is meet and greets, from which I've met a few very interesting gals.

Read a few reviews, look at the website and any other ad site or twitter feed available for more pictures. The more photos I see the better. Twitter selfies are gold, because it's the real person, not glam shots and often recently taken

Pictures first (where ever they are), rates next, and reviews to be sure she is real and doesn't have a bad reputation for flaking.

Google her?  Yes
Follow on Twitter?  No, but will look at her Twitter if a link is available.
Read board posts?  Not as a search, but I may be aware of her board presence.
Visit website?  Yes
PM reviewers?  I have, especially if there are no recent reviews.

and occasionally 3 and 5.  I may do 1 to see if she has ads anywhere else.

Very interesting.

Btw, you have some great articles on your website, I'm always entertained.

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