Ferrets have been domesticated since the time of the ancient Greeks. Don't bathe ferrets weekly; their skin gets too dry and their odor increases. Bathe less often but clean bedding very, very often. Ferret kits are almost always sold too young for their rabies shots to have been provided yet. They need 3 carefully timed CD vaccinations in their first months, so the usual purchased kit needs 2 more CD vaccinations and later their rabies vaccination. Shape ferrets toward good behavior by encouraging them, and use short times out for bad behavior. Medical care for a ferret often adds up to $5,000 over a ferret's lifetime. The number of pet ferrets in the U.S. during part of the 1990s was estimated at 7 million.