Figure out what you feel you need to see from a lady's reputation to feel comfortable seeing her.  

Some say she needs at least 6 reviews, while others have a minimum of 10 from established reviewers.  Then there are the experienced guys who trust their instincts enough to see a brand-new lady, or one lacking any reviews anywhere.  
A lot of folks will avoid any providers who don't screen, but then some will disregard that as long as she has other things that speak for her.

It's totally all over the place and so is screening.  

You've got ladies who don't screen at all and providers at the other end of the spectrum who have long forms which must be filled out and sent with scans of your photo ID.    So you need to decide where your screening comfort zone is too.
How much information do you feel safe in handing over and to whom?  Some men won't ever give out their real names, others will supply it to a verification service but not individual providers, the opposite who don't want a site to have their info but WILL give it to select, established & reputable ladies, and then those who will give it out to any verifiable entity who "asks nicely" lol.  

I require real-world info plus verifiable references from established providers.  Sometimes I need more as it can be a case-by-case sort of thing.  Newbies MUST be screened by one of my preferred verification services and give up a LOT of personal information.  

But my requirements are NOT standard.  It's simply what works for me.  :-