Honestly I'd push back on your cousin here, learning git the first week is way more useful than waiting until loops feel easy. Loops you can practice on your own time, but a group project dies fast if you can't pull and merge, and that pain is what actually teaches git anyway. Three months of delay for a tool you could pick up basics on in a weekend just doesn't add up in my experience.

The squeak usually means the wax is rubbing dry, so a touch of beeswax on the folds may quiet it.

Been there man and it flat out sucks. Same thing happened to me on a 30 unit place off Broadway, every breaker just said "lights" in that lazy builder sharpie. What saved me was plugging a lamp or vacuum into each circuit and flipping breakers one at a time, then writing the unit number right on the panel cover with painter tape so it never happens again. For the devices, grab a tone generator with a good amp probe and just work one zone at a time, start at the panel and chase it out. Doing it solo is slow but it beats dragging a helper around who just stands there. Hang in there, two days sounds about right for 60 plus devices, sadly.