Hi Gail,
Looks like you got it sorted for the Single Listing page.
There is an issue with the enfold theme where it only displays one listing per page for custom post types. Can you post a support request with them as to why the theme only shows one custom post type per page.
I’m unfamiliar with their template building system and if you can get some sort or guidance from them I can give you a hand implementing it.
(Also before uploading files, zip them up first) php files are a security risk.
Q. I am using content-listing-single.php in the WordPress plugin folder as when I copy it to my child theme it does not work (I have obviously made an original back-up copy too).
A. For this to work you must create a folder inside your theme called /easypropertylistings/content-listing-single.php
Please zip the template files and re-upload.