Price has only been mentioned a few times here and it was just for a quality dog, or at least quality bloodlines.
The initial cost is so minor compared to the money you will spend over that dogs lifetime. Wait until your dog runs into a fence, or sticks a stick into its chest, you will then find out what it costs to have a dog. I don't mind saying I am well over 12,000 in the last two years and lookling at 5,000 more in the next month for a new hip for my dog.
Even without anything major happening, vet bills for regular care and the occasional accident will add up. And for proper care of a companion these things are a must.