I’d like to monitor 6 heat pumps at a commercial property, mainly to aid in sizing replacements when needed.  They are each fed by a separate panel (or possibly two are on the same one), and most of those panels are in tenant space (where our wifi may not reach), so using power monitors at the panels is not ideal.  What are some other options?

Other possibly relevant background info:
Outdoor units are all in a line, spread over about 60 ft.
The heat pumps are really the *only* things I care to monitor (except maybe for the one gas furnace as well).
Heat pumps are all single stage.
It would also be nice to have live information to remotely check for any anomalous behavior, but that’s not a priority.