That is really crappy luck. I have stood a few clients up at the last minute due to unforseen circumstances(however I always call or e-mail to let them know) I get more stood up by clients though....

I wouldn't have left 4 messages, and DEFINITELY not have waited 1.5hrs!Sorry bud, but chances now she thinks you're 1)desperate 2)creepy   I'd leave her a bad review if possible and not schedule with her again.

I think you just get bad luck. Chances are a provider who has good reviews is NOT going to stand you up or screw you over...but you got the short stick.

Move on a keep trying to find that provider who is reliable and satisfies you!

However, 3 times in what appears to be a relatively young hobby career is abnormal.  Maybe you need to re think your approach.  Don't really know what else to say. I've been ncns'd  and I know how frustrating it is.  When I make the second call, and it goes to voice mail, I usually just tell the lady I'll Wait for her call back. I try not to sound frustrated, even though I am.  I don't call every 5 minutes, I call back 15 minutes later and tell her I'll stay a little longer than I leave.  You can read my reviews of Taylor and Hope to see how I was rewarded by sticking around.  One was in the shower, the other had bad cell phone reception in her new in call. Good luck

If you travel a distance as I do, or special circumstances, you need someone who really makes & keeps appointments.  Some girls...  unprofessional in my opinion...  work on a first arrival basis.  They say yes to everyone & the first one to arrive gets in & she shuts her phone off.   When she's done, she turns her phone on & starts over.   Typically they do not call back those they've NCNS.   If I see in review details that a provider is hard to get a hold of, that's a warning flag.  

You were right to not side outside her location.  Because I travel a distance, I try hard to arrive early to allow for delays...  Once I find the location I remove to the nearest coffee shop & return with just a couple of minutes to spare.  If I miss a connection, after 5 minutes, I'd withdraw to the same or similar location.  If I'd already been into the shop, I might make another small purchase (with cash) and then sit in the lot to wait.  I would bail at 15-20 minutes in most cases...  unless I heard from her.

So I'll give you credit for NOT sitting in a hotel lot, drawing attention to yourself.

Even if a provider is newbie friendly, they should still screen...  they just use alternate means to do so.  
skb

normally patrol parking hotel lots.  A guy sitting in his car waiting for the hour to be up, will draw attention to himself & probably to the lady you want to see.  LEO will not have marked or undercover units parked in the lot.  AVOID motel type locations where individual rooms can be tracked from the outside.  By all means, driving through the lot with your eyes open is fine.  If you want to observe the location do so from the outside or drive by on the street.  
I was seriously eyeballed by a cop in a marked unit when I was getting out of my car on the way in to see a lady.  I mentioned it to her & she remarked that hotel management had requested extra patrols due to thefts from guests cars.  So I guess a guy sitting in a car might look like a thief or maybe a mugger.  
Sitting outside her incall is not discreet.  Everything about this hobby is about keeping everything discreet.  
skb

I'm convinced that hotel management generally knows what is going on with regard to incalls.  Outcalls to your hotel room (costs you more) they can not be sure if you're having an affair or a provider.   Mgt likes the extra income...  but NO mgt can withstand public knowledge of their tollerance of prostitution.  

What can happen?  Worst case, hotel management calls LE.  They harrass you or her or both...   try to get enough for a bust...  
Best case, hotel management kicks her out...  tells her she is not welcome there.  I know ladies who have been forced out.   There are only so many hotels in an area...
skb