This 10-inch Ant-man is still short for the 4-inch line, what more for the 6-inch figures? Any self-respecting 6-inch Marvel collector would find a better option for an Ant-man. When they realize that it's in bad scale, 6-inch collectors will let go of this 10-inch figure. Since the 4-inch figures is a dying scene, at least for the Marvel-Hasbro line, the demand won't be high.
If you're still hunting for this figure, just wait it out until you get an good deal. You'll live even without one anyways.