I think very few people buy Duck books for investment. There might be a few like WDC&S #1 and FC #386 which. over a long time, have a good return but the rest are too market/buyer sensitive. I remember Overstreet's notations saying, "Prices vary widely on this book." Really that should be on all the Disney GA. Some dealers swear you cannot move them for guide and I know another one that will take every duck book you have, in nice shape, and swears he can sell them for a tidy profit. Many, most?, dealers do not bother bringing Duck books to shows because they just do not sell regardless of grade. However, the last Duck book I bought was from a major dealer at a small show. Figuring out Duck prices and sales trends is confusing.