What is the ruling on buying a house from a company in installments, with the company stipulating the payment of a sum as a bank deposit, the profits of which are spent on site maintenance?

There is no objection to purchasing apartments by installments at a higher price than the cash price, and there is no objection to apartment owners sharing the costs of general maintenance for their homes. It is permissible to pay the maintenance fee to the company if its role is supervisory, and the money remains the property of the apartment owners (cooperative insurance). Any surplus from it must be invested in permissible projects, and its profit distributed among them or added to the fund. However, the company owning the money is not permissible, because it falls under the category of forbidden insurance based on Gharar (excessive uncertainty).