Price guide for vintage computers

Has anyone considered that creating a price guide might do more harm than good. What do you think that thrift shops (for example) would do if they had a price guide? Jack their prices up to match most likely, on items that they might have sold for less if they didn't know better. I guess my point is that having a price guide available online might lead to higher prices. I was able to buy a valiant turtle robot for a fraction of what it was worth because the seller had no idea of it's value. Every collector has similar stories, and while those things would still happen from time to time, a price guide would certainly reduce the chances -especially with software. If the price guide lists certain things as rare and more valueable, then the seller will likely jack up his asking price. On the other hand, what if the seller had no idea? The chances are better for collectors to get a "good" deal. It's just something to consider. E.