[bars] Ground tester?

[William Smith]

One of my neighbors in the Turks & Caicos appears to have taken a lightning strike which blew up a few thousand dollars worth of internet connectivity parts.

I'm in discussions with his electrician about what kinds of ground are appropriate for his VHF radio and Ethernet lightning arresters (big wires, short runs, no bends, loops, or coils, directly to the nearest ground), and I'm not sure he's even interested in making sense of the wiring mess that's extant, but I thought it might be instructive to use a ground tester (Earth Resistance Tester, Megger, etc) to see if the various grounds are even connected, much less good RF grounds.

Has anyone used something like https://www.amazon.com/Best-Sellers-Ground-Resistance-Meters/zgbs/industrial/5011685011 to test grounds, are they useful, and can they tell a good RF ground (as above) from a coil of wire that's electrically connected to ground?  They seem to range in price from a few hundred to a few thousand, so I've sent out feelers about renting or borrowing one.

If this is the wrrong tool for measuring RF Ground Impedance, what is the right tool (or procedure) for doing so?

Thanks!

73, Willie N1JBJ