What is the ruling on buying a house in installments if the third and fourth installments are paid directly by the bank to the contractor, on condition that the buyer repays the bank the amount with an additional 1% interest?

The aforementioned contract is impermissible due to its inclusion of a usurious interest (riba), and in terms of prohibition, there is no difference between a little riba and a lot of it. An exception to the prohibition of riba is made for someone who is compelled by dire necessity to engage in it.