As you have shared no information about this deed, how it came to be executed, delivered and recorded without your knowledge, or how it overrides the quitclaim deed you believed to be valid, I cannot comment on those issues. Your post suggests that your brother is in agreement that the quitclaim deed is not valid, and if that's the case then there is no need to go into those issues.
Have you considered getting an appraisal, and asking him to pay half of the appraised value?Quoting blueamber
Litigation is expensive. But if you win, it could create significant issues for him, given that he has a tenant in the property who could potentially sue him for breach of contract if the court orders the property sold.Quoting blueamber
Your position on routine expenses would presumably be that your brother (through his tenant) has had exclusive use and enjoyment of the property, and that he should thus bear those costs. For improvements, it would depend upon the improvements and their effect on property value. For any claim of reimbursement, you might try to assert that the claim should be barred by virtue of your brother's apparent fraud and concealment of your rights. These are issues to discuss with your lawyer.Quoting blueamber
As a co-owner, who did not agree to the tenancy, you would normally have the right to the use and enjoyment of the property, with the impact on your brother's tenant being something for him to work out with his tenant -- but we don't know the details so, once again, that is something to discuss with your lawyer before you act.Quoting blueamber

