Is it permissible to sign an undertaking with an Islamic bank to purchase an apartment using the Murabaha system?

If the bank first purchases the apartment for itself, then sells it to the prospective buyer after it has entered its possession and responsibility, then this is permissible. It is permissible for the bank to obligate the prospective buyer to sign a commitment to guarantee its right, because obligating fulfillment of a promise in a Murabaha transaction for a prospective buyer is religiously permissible. However, a binding promise from both parties is prohibited because it is considered to be in the meaning of a sales contract before possession.