They used to pop up somewhat regularly around here, heck when I bought mine I had test driven another black RC the same day I checked out the one I bought (I always end up buying the second vehicle I look at for some reason), but even before the supply shortages they started getting harder to find.
If you want one in amazing condition mine wouldn't be the one for you. Mechanically it's quite solid, I've done and had done loads of mechanical work and upgrades to it over the years. Rebuilt engine with new gaskets, hoses, seals, rebuilt turbo, replaced everything in the suspension/brakes, etc. Put in a carbon driveshaft, upgraded center diff, the list goes on. I've also accumulated a large pile of spare stock and aftermarket parts for it. I have two different BBK adapter kits on a shelf lol. But cosmetically it's definitely got some flaws. A couple small rust patches on the body from poor repair work some previous owner had done, some scratches to the paint, and it definitely had a small accident on the front right corner at some point.
In my (biased) opinion it's a solid "drivers condition" car. Long story short I used to baby it but then realized there's no point in babying cars so I started using it for the TSD events on back roads and I'm very glad I did. These cars are an absolute blast on loose surfaces with the torsen LSD in the back.
I'm rambling a bit here but after 11 years I have a lot of thoughts on GTFours rattling around in my head lol.