Against the owner of the thing, his right is in the nature of that of pledge, by virtue of which he may retain the thing until the expenses, which he has incurred, are repaid.
He possesses this qualified right of pledge, even against the creditors of the owner, if they seek to have the thing sold. He may refuse to restore it, unless they either refund his advance, or give him security that the thing shall fetch a sufficient price for that purpose.