Is it permissible for a non-Islamic bank to purchase medical equipment and sell it by installment with a price increase over its original value?

It is not permissible to deal with usurious banks except out of necessity or pressing need. Selling by installment has two permissible forms: The first is that the commodity is owned by the seller (the bank) and is in its possession, so it sells it to the buyer for a known price that is not subject to increase. The second is that the buyer requests the bank to purchase a commodity from a third party, and then the buyer purchases it from the bank after the bank has acquired ownership of it and it is under its guarantee, for a known price that is not subject to increase if payment is delayed.