I agree with all of the above, and particularly with medoraman's sentiments. Buying a mixed lot, unattributed, is a blast! Searching out the attributions is a ton of fun and a great and inexpensive way to learn, at least for late-ish Roman coins.
Sorry I was a bit short when I said the price was high. I wasn't trying to be insulting in any way. I have also paid too much for a ancient coin in the beginning. But then I got the coin that I wanted and I was really happy with it. Although more than a few of us somewhat pride themselves on getting good deals, even myself with a very low budget. We also try to help others get good deals as well.
I know many here like to buy uncleaned lots, and the seem to have a good time. However, my experience with these lots is not so good. Generally, over half of the coins are culls wit no way to attribute them. The other half are usually only marginally better, but not worth the money I spent. I think I'll stick to coins I can identify/read and leave to uncleaned lots to ya'll (that is, if I ever get off this darn wagon).
To clarify, I was advocating buying mixed lots of cleaned but unattributed coins. I also thought cleaning dirty coins would be fun but found, as you did, that most were not worth cleaning.