The most I ever spent on a PowerPC Mac was my PowerMac G5 for $265.99 in 2011. Thinking about it now, in 2011 and 2012 PowerMacs were routinely going for $150 to $200 on eBay and locally but parental restrictions made me order it from a regular vendor like Newegg or Amazon. I ended up getting it off of Newegg and my mother bought an extended warranty (which worked out later on).
It turned out to be a dual 1.8 GHz model with 2 GB of RAM and a squealing 250 GB HD. I threw in 2* 1TB drives (one boot, one storage), upped the RAM to 3.5 GB out of spare RAM here, and loaded Leopard. I never realized just how bad the Nvidia 5200 (AGP) is until I ran dual displays off it.
That machine died and the warranty bought the machine back for original purchase price. We only lost the $45-$55 that my mother paid for the warranty itself. They didn't even want the machine back and with a failing PSU and BGA on the logic board neither did I. I removed my RAM, video card (to keep as a spare), hard drives, optical drive, heatsink covers (as a keepsake of that machine), acrylic side panel, and side door as well as the optical drive door.
That died around December 2012 and I still wanted another G5. In March 2013, my mother ordered a new G5 for me from Mac of All Trades for my birthday. This one cost $99 + shipping, so $140 or so. It is a June 2004 dual 1.8 model with an ATI 9600 XT and 2GB of RAM. I installed my hard drives, RAM, optical drive, and the optical drive door onto this one (existing door was bent slightly). It now has the dual 1 TB drives, the ATI 9600 XT, 4GB RAM, and soon to be an SSD. I am running it to this day and typing the response on this one.
Were these machines too expensive? Maybe but I love them to death.