Is it permissible to buy a car for work and to increase income by depositing capital in the bank and taking a loan guaranteed by it, provided that the bank buys the car from the showroom and then I buy it from the bank in known installments, given that its price in this case is less than its cash price?

It is permissible to purchase a car through a bank if the bank first buys it for itself, and then sells it after taking possession of it from the car dealership, provided the contract is free from usurious conditions such as a late payment penalty. It is permissible to deposit money in the bank as a guarantee for installment payments, or to reduce the bank's profit, or to benefit from the deposit's profits if the bank is Islamic. However, if the bank is interest-based, it is not permissible to deposit money in it except in cases of extreme necessity and when no Islamic alternative is available. If the bank is Islamic, the deposit must be in an investment account and not a current account, so that the contract is not invalidated by a loan condition. It is permissible to mortgage deposits (current or investment), provided that the amounts from the current account are transferred to an investment account due to the absence of a guarantee, and to avoid the mortgagee (creditor) benefiting from the growth of the collateral. The institution may also request legitimate guarantees from the client, such as a third-party guarantee or the mortgaging of an investment deposit. It must be noted that this transaction is a Murabaha sale and not a loan.