has anyone done a study to discover the monthly bandwidth usage (24x7xdays in month) of an average (if such a thing exists) repeater system?

Reason I'm asking is I have a site for which there is no possibility of getting wired internet access, and may not work, due to physical interference, of standing up a 5.8 shot back to our hub site.  This leaves a hotspot or commercial 4G access point...and want to make sure we aren't going to be bumping against traffic caps or excess data charges. 

How have others handled this?  

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