My Sam (16 at the time) had dropped from 13 to 9 without me really noticing. He didn't look any different, really, but I had decided to have him examined rather than just updating his shots. His kidneys were down to 10% functioning - a prescription diet kept it there for two years.

His last two months or so he was starting to look like a dinosaur - every disc in his spine stood out like a crest and you couldn't pet him along the spine, you only bumped along it.
At the same time, his belly looked a bit bloated.

He was happy and healthy until the last few weeks.

In hindsight, I wish I had been paying closer attention: I might have caught the kidney issue earlier, although I'm not sure that is what ultimately took him from me.

I totally understand the "vet bill" issue, especially now. Being unemployed with one's mother having to help because unemployment doesn't pay the bills sucks hard - but we're talking our cats health here.

Is there a walk-in clinic near you?