Do you have any pictures of it? It's hard to say without knowing the condition and age. Yellows are pretty rare and people around here (WKC) would probably value them more than many other colors. Overall, a weber kettle probably isn't really going to be worth that much unless its very old (50's probably), an almost extinct model (Westerner, the One that looks like the well, etc.) or new in the box. Regardless, a yellow in any condition for $15 is a great deal! Clean it up and enjoy it for years! And they turn to an orangish color when they get hot!