What is the ruling on purchasing a spacious house through Islamic financing, where the house is bought in partnership between the buyer and the financing entity, and the buyer pays his share monthly with a profit to the financing entity, until he fully owns the house?

The participatory method known as diminishing Musharakah (diminishing partnership) is Islamically permissible if it adheres to the Sharia-compliant regulations. These include that neither party commits to purchasing the other party's share at its original value when the partnership is established. Rather, the price is determined by the market value on the day of sale or by agreement at the time of sale.