Ebay is a great way to gauge what your collection might be worth. I am a firm believer in that something is worth only what people will pay for it. Who needs a price guide when you can look on ebay and see what people are actually paying for them.
You can't put a price cap on a market like this for a couple of reasons.
1. This is a free market item we are talking about and to try to put a price cap on a free market is as unethical as "scalping", i.e. Hoarding an item in hopes of artificially hiking the overall price and demand for the commodity.
2. Even if we wanted too, and together, all 100+ of us on this board and the email group tried, we could possibly drive the price a few pennines closer to whatever price we set, but all in all it wouldn't make that much of an impact. But that still has no effect on someone willing to pay a higher amount for favorites or guys needed to complete a collection.
Generally when we do a tansaction in the group it stays between .50 and .75 per M.U.S.C.L.E. or we do a trade for it. As far as folks not in the fold yet, they tend to pay a higher price. This situation is similar to collective bargaining, because we do have some control over the prices we give each other in our group.
I will tell you this though. If the Kinnikuman cartoon is a sucess, I foresee MUSCLE's going up to $1 each average. At least for a limited time. My suggestions, buy in bulk, and look for Buy IT Now or misdescribed listings to get a better overall price. I have thousands of MUSCLEs and my average purchase price is .51 cents.