Thank you for your question.
The IRS may place a lien on any property that you own regardless if there is a co-signer on the loans. If you are a joint tenant or owner, that is the co-signers name is XXXXX XXXXX the titles and deeds, the IRS may place a lien on your ownership interest in the property. If you are not a tenant in the entity or a tenant in common, then they can force the sale of the property and split the money according to the ownership interest and offset your share with tax debt.
NOTE: in realestate you can only be a tenent in the entirety if you are married to the other owner.
NOTE: for tenents in common the lien remains in place until the property is sold and will survive you even in death as the property is passed to heirs.