The Marshall Farms Guarantee states that : This warranty does not guarantee against colds, influena or any other bacterial or viral disorder. Also not covered are conditions caused by parasites or other acquired diseases growths, tumors or cancers. Any medical or surgical expenses that fall under the Marshall Guarantee will be reimbursed through the place of purchase and WILL NOT EXCEED THE ORIGINAL PURCHASE PRICE OF YOUR PET. (Emphasis mine). The way I read this, if your ferret cost $100-$150, that is the maximum reimbursement that the guarantee permits. Most pet stores will offer to 'replace' your ferret with a new one. Not much comfort, if you have already bonded to the little fert. I would not worry about invalidating this guarantee--it is not worth much anyway. Carol [Posted in FML issue 3248]