Penlights that double as lug wrenches, the latest buffalo meat and chocolate cream pie diet book - ever wonder why all these questionable items are grouped together in the checkout lane?

The answer is pretty simple: all of them fall under the heading "impulse purchasing" - things we buy on impulse, without taking the time to consider their usefulness. We are all susceptible. If you don't believe it, look in your garage or "junk drawer."

While most impulse purchases are harmless enough, some are anything but trivial. Consider an addition to the family - of the furry variety. Often, well-intentioned people see a hamster or ferret that captures their heart and, without considering the ramifications, impulsively take the animal home.

The expense of owning a pet is probably the most overlooked consequence of any pet-owner relationship. Advances in pet care, especially in the development of pet foods and medical research, have caused ownership costs to increase over the last 10 years. Since it's not likely that this trend will reverse itself any time soon, potential "pet parents" should consider their finances before taking home a new pet.

All owners need to provide the basics of professional medical care, quality food and adequate shelter. The only other necessity for a responsible owner to provide is love - and that's free.

Listed below are approximate costs of basic care for small mammals. Costs can vary widely, depending on where you live and specifics associated with each individual pet.

Cost of Small Mammals

Of all of the unconventional types of house pets, the ones that probably owe some of their popularity to their reasonable price are the so-called "small furries" - gerbils, hamsters, guinea pigs, etc. They can be easily found at most pet stores and they don't require major investments in feeding or care. While some purebred lines are established and marketed as such, most that are purchased as house pets are hybridized individuals.

Annual Costs

Veterinary Care - $25 to $50
Immunizations - N/A
Feeding - $15 to $50
Miscellaneous (cage, toys, etc) - $50 to $75

Total: $90 to $175

Note: Because these animals have relatively short life spans, you should consider costs of replacing the pet.