Typical prossie behaviour. Take every booking and whoever turns up first at the door goes in. Then a maid / friend in the flat comes up with a story why she isn't available and assumes you will wait.
If us punters hang around while they service another punter we add to the problem.
Well done for walking, I tend to do this now as soon as I get the "I'll be five minutes" response. I did it the other day and got a text back 2 minutes later saying "come now". I had already driven off so told her, sorry I've gone now - Touché.