I was unable to add a followup after the issue was fixed since that would have been a double reply. I’m trying again now a year later since that limit might have timed out.
After nearly a year of fighting with the HOA, last year I finally convinced them to disassemble the shared meter panel to check it.
And y’know what?
The neutral lug for our meter drop was stripped out and barely contacting! Though the proper fix for UL compliance would be to replace that part or the entire unit, that’s too expensive for them. So my electrician drilled it out, tapped it for a larger thread, and installed a new lug. Tada, problem solved!
The problem was exactly where I’d been telling the HOA management company for months - apparently he was absolutely flabbergasted when the electrician was on the phone with him. And since I use the same electrician as they do, they trust him.
Throughout this process sense was absolutely invaluable. The only other way to collect the necessary data would have been to buy a high storage capacity recording oscilloscope, install safe voltage test points for my interior panel, and leave it collecting for weeks. There’s absolutely no other way this would have gotten fixed when the power company AND multiple electricians from separate companies could found nothing wrong on their own.
Now that it’s fixed and my neighbors know about the saga, I’m hearing about others with bizarre power problems that nobody can solve. I’ve been telling them all to get sense.