I co-signed for my sister for a car loan. The car was repossessed and now the bank wants me to pay. I understand that it is my responsibility, but I don't have the money. My sister is out of work due to a back injury and is also trying to come up with some money. They have threatened to seize my home to satisfy the loan. Can they actually do that to satisfy a $9k loan?

No, but they may be able to place a lien on the home.

No, this is just threats, They really want you to set up a payment plan with them. * OK really want a check for full. But if you don't do something, they may well get a lien against your home.