Went through something similar (but much cheaper) a couple years ago. Drain line would back up into the basement periodically (nowhere near the guitars, thank goodness). Had a company out who said they found a complete blockage under the garage floor and would have to dig up I don't know how much drain line. Had another guy look at it, said we only needed to do what was under the garage floor. Still one of those wow moments when we got the estimate. He dug up the floor and yelled up, "I think you need to come down and see this". Went down and looked, you know, with my vast plumbing knowledge, and the problem was fairly obvious. The pipe was gone. Not broken or crushed - gone. He said, "It almost looks like there was nothing here, and honestly, I don't know how anything ever drained." Works like a champ now.
Just rejoined the car payment club myself. Replaced a 2004 Buick Terraza. Too many little things adding up, and it had a nagging ABS/traction control issue that I was not willing to put big money into. So I'm into a brand spankin' new ride for the first time in 10 years, and with all the new stuff, it's one of those "why did I put this off so long" moments. The "oh yeah, that's why" came with the first payment.