Is it permissible to purchase a car through a bank that buys and then leases it out via a lease-to-own system, with an upfront payment and monthly installments deposited into its account, considering that this bank's percentage is lower and it guarantees the car during the lease period?

The decisive factor in contracts lies in their meanings, not merely their wordings. Therefore, if a bank executes an Ijarah Muntahia Bittamleek (lease ending in ownership) contract, structured according to Sharia principles, there is no objection to dealing with it, provided it is not an usurious bank. However, if the transaction is not structured according to Sharia principles, or if it is merely a contractual name used to conceal usury, then it is impermissible. Similarly, if the bank is usurious, it is not permissible to deal with it, even if the transaction itself is permissible, due to the lack of necessity, as it constitutes cooperation in sin.