Been reading and trying to do my homework.  Did I miss an obvious red flag or was I too jumpy.

Found a provider on Backpage that I could match to a pretty close picture and phone number on TER.  Five reviews between Nov and Mar.

Called and left a message with 1st name and got a return call at the top of the next hour.  Set an appt for several hours out.  Asked if she'd seen me before but didn't ask for references or personal background.  Red Flag?

After 2 calls, was pulling into the parking lot of a mid-range hotel and then made the 3rd call for room number.  Noticed what appeared to be an unmarked car.  Then look around and saw a marked crusier parked way back behind some trees.  Left immediately.

About 10 mins after my 3rd call she started callling me.  Finally decided to answer on her third try and told her things didn't look good.  She said she wasn't a cop, I said they were in the lot, and she said they're always there (which I don't buy at all).

It's a tough call when your a newb, but you did the right thing. Always better to think with the big head, instead of the little one.

All that mattered was that the cops were there.

You made the right decision.

I stick to well-reviewed, seasoned providers on Eros, Cityvibe, BigDoggie and TER. I've never had a problem.

Five reviews is bare minimum. Did you check to see if the reviewers themselves made multiple reviews? If most of them were single reviewers, too chancy for a newbie.

Look for those who are newbie-friendly and have multiple PAGES of reviews. You want your first experience to go as smooth as possible.

If it really is true that cops are always there, then she should be booking in a different hotel. Someone who doesn't ask for any references or some other sort of info is someone who takes chances. Not good for her or you.

and I'd recommend an outcall over an incall first time out.. Book a room in a decent hotel...

Good call.  Unfortunate but better safe than sorry.  I'd not have been able to relax & enjoy under those circumstances.  
sjb