Is purchasing a car and paying half its price to a tourism company, which then leases it back to me annually for five years before transferring ownership to me, permissible or forbidden?

This transaction is not permissible because payment must be made through a legitimate means, and it is not permissible to rent something you own. The company can buy the car and then sell it to you through murabaha (cost-plus financing), and the car becomes your property as soon as you purchase it. The company may retain its name in official documents for licensing necessities, while proving your ownership of it. The Council of Senior Scholars has permitted the seller to keep the car's registration for documentation purposes.