Thanks for posting, Happycamper. We can all learn from professionals and retired guys have a lifetime of experience under their belt.
To me, it sounds like the OP will have some sorting out because of the previous owner's work. I experienced the same when I bought my own old house.
Try this: My old dwelling had knob and tube for most of it's life. The previous owner had installed a more modern load center and pulled some circuits with NM-B (Romex) but the lights and some receptacles were still powered by knob and tube, dropped from the attic. When I pulled the paneling from the attic stairwell, I found an old disconnect box used as a junction box. A single cloth insulated wire was led into the box and the cover held that wire, crimped by the paneling that was installed over the box. It's a wonder that there was no fire.
I'm sure Happycamper has some stories about what he's found, also. I'm a Residential Contractor and have found really substandard electrical, plumbing, and mechanical issues.
