You paid $40 for two BW chicks?
Well, I'm going to disagree with your statement. I sell purebred Ameraucanas for less than that even full grown birds!
I paid 50 once for a BW pullet and I will never do that again. I was ripped off big time on that purchase and it was a listed breeder.
I guess it all depends on what people will pay in your area, but around here, I'm lucky to get bites on $4 a chick and people will rarely pay more than $15 for a pullet or hen (lucky if I get that), purebred or not. I think $4 is pretty dang cheap considering you pay at least $3 at feed stores for chicks that aren't even labeled what breed they are most of the time. Usually just sex linked chicks I would think. It seems to be the same breed of birds every year.