You can find a puppy from untested parents of questionable conformation and temperament for $400 or less, but why would you want to? Shouldn't a "just a pet" puppy have just as much of a chance at a long, healthy, happy life as a show or breeding prospect? Is it any less tragic when a beloved Boxer drops dead at 3 years of age from ARVC because he was "just a pet"?
Responsible breeders don't do what they do for the show/breeding prospects - they do what they do because they love the breed and believe that *every* Boxer (and every Boxer owner) - pet or otherwise - deserves a long, healthy, happy life. If you're going to spend money on a puppy, spend money to support those breeders, not the ones who don't care - or are clueless - about the breed.