4 years is a new- wait- it's not even a breed! You may love your mutt, and I love mine, but no way do the sellers deserve $2000 of anybody's money.
Want a calm, obedient dog? Then train your dog and exercise him and VOILA!
I have two of them.
Instead of "educating" us, why not go here:
http://www.nopuppymillscanada.ca/ and learn something for yourself.