House constracted by me but my brother wants a share..

Several years ago, I acquired a piece of land, wherein my brother made a modest financial contribution, resulting in a shared ownership arrangement. Subsequently, I undertook the construction of a two-story dwelling on the property at my own expense, while my brother did not contribute any funds towards this endeavor. Despite numerous inquiries regarding his financial commitment, he has consistently deferred discussions for future consideration. To date, I have solely borne all expenses associated with the property, encompassing everything from electricity to water bills, maintenance, and other related costs. Recently, my brother has expressed a desire for exclusive ownership of one floor of the constructed house, asserting his claim to the property as a whole. In light of the circumstances, I have maintained that he is welcome to construct additional floors at his own cost, given that I have funded the entirety of the project thus far. I possess all relevant documentation substantiating my financial contributions, while my brother lacks any supporting paperwork. Considering the complexities of this situation, I am seeking your professional advice on the legal recourse available to me. Specifically, I would appreciate your insights on the appropriate steps to take in order to safeguard my interests and ensure a fair resolution to this dispute.