What is the ruling on selling a car by lottery for half its price to benefit the buyer without causing loss to others?

It is not permissible to sell a car for less than its value to someone who buys another product and enters a draw, because this falls under gambling (qimar) and games of chance (maysir). In such a scenario, the buyer pays money for a product they may not need, or pays more than its actual value, in the hope of winning a discount. This involves a certain loss (ghurm muhaqqaq) and a potential gain (ghunm muhtamal), which is the essence of prohibited gambling, something Allah has associated with idol worship, intoxicants, and divining arrows.

As for participating in draws for prizes offered by stores, it is a condition for its permissibility that a person buys the product out of genuine need for it, not for the sake of the prize, and that the product is not sold for more than its actual price. If the seller raises the price of the product because of the prize, then it is not permissible, as this places the buyer between profit and loss, which is a form of maysir. However, if the seller sells at the market price, and the buyer purchases the product out of need, there is no harm in that. But if the buyer purchases the product not out of need but solely to obtain the prize, this is a waste of money, and the Prophet, peace be upon him, forbade wasting money.