What's the life expectancy of a guinea pig? Can't be more than 3 years, right?
Waaaaaaay back in the day, my girl and I bought two gerbils on a whim (Rodney & Peete). One of them got sick and was pooping blood after a day or two of owning it. Took it back to the pet store and the employee said that they would take it in the back and do all that they could to see what was wrong with it, and they would give us a call. Obviously, the gerbils became snake food because we never heard back (got our $ back, doe).
Anyways, to answer your question, I spend A LOT on my two dogs. One has been battling bladder cancer for close to a year, so the vet bills can be pricey.