I have been watching iMac G3s from time to time on Ebay and depending on colour and condition they go from 50-150EUR (if you are in Germany at the moment, when buying). But personally I would still wait for a good luck buy, an auction that ends around/under 20,-EUR.
- It will most likely be the dark blue ("indigo") or the blueberry (torquoise), but be sure to get the DV one, with Firewire, there was a later "indigo" DV-model only with USB, and the early blueberry coloured had USB only, too. But I think you could distinguish them by their 350MHz). -
Maybe with personal pickup near you. The state were you currently live and Nordrhein-Westfalen and Berlin come up very often as locations of Macs.
If it's the grey one (graphite) you want, especially, they often end around 50,-EUR, but can be had for 30,-EUR, too, if you have time.
Do you have a special Processor speed you want in the grey one or does it just have to be an iMac G3 DV (or any colour?)?
I already have a lime one, for years, so maybe this is the reason I would only give 20,-EUR for it. If I would be searching for one now, maybe I would give more, but on the other hand I am a cheapskate, too, so....