Did you try PropertyContactEmail. there are a few endpoints that you can force even if they don’t show up. 
 

opportunity tags aren’t available in proposals though & that’s quite frustrating for me. 

​@Kbaird...I tried to implement your suggestion but maybe I don’t understand what you mean by “you can force...endpoints”.  I entered “PropertyContactEmail” in several fields on Web Report Designer but couldn’t output the Property Email Contact’s email address.

If you can clarify or suggest more, please…

For now, I’m setting up Contacts - in an unnecessary, impractical way if you ask me - for Properties so that I can get the layout we need.  So it’s Report Designer vs. Company Policy/Practice.