The term "breeder queen" has different meanings to different people, and thus different price tags associated.
To some, a breeder queen is an unproven, untested new queen from the breeder's most desirable genetics. In other words, a good place to start in breeding. Generally, these aren't that expensive, and usually run around the same price as a good "average" queen.
To some, a breeder queen is a proven, tested, monitored queen from the breeder's most desirable genetics. Usually, it's the first category that is put in a nuc or hive and allowed to lay a few rounds, or a few months of rounds, while the breeder judges her laying ability and (hopefully) offspring to ensure the desired traits are being passed on. Generally, these are more expensive. A few hundred dollars+.
To some, a breeder queen is an Artificially Inseminated (or Instrumentally Inseminated, depending on your lineage) queen, taking the most desirable virgin queens and inseminating her with genetics from your most desirable drone stock. Typically these are not tested or proven (as AI queens don't lay as long as open mated queens), and come with some decent price tags, depending on the genetics, skill of the breeder, and quality of the product. Usually several hundred to a thousand.
Lastly, to some, at least that I've heard of, a breeder queen is an AI/II queen that has been proven and tested. These are your money queens, as Dwight Schrute would say. Big bucks here. I've never seen anyone market or sell these.
Generally breeder queens are sold "as is." No warranty that they will either be accepted into the new hive, or that they'll be great breeder material (as that term is very subjective anyway). If you have a long standing relationship with a breeder, that may change, but it isn't the norm. [/QUOTE