How legitimate and valid is a murabaha transaction involving the sale of sand, with a mention of the reason?

"Murabaha sale is the sale of a commodity for the price at which the seller purchased it, with a known increase. It is permissible by consensus, and its conditions are the general conditions of sale. As for the Murabaha to the purchase orderer sale, which is conducted by some banks, it requires the buyer to promise to purchase a specific commodity, then the bank takes lawful possession of it, and then sells it in installments with an increase in price over the immediate price, provided there are no forbidden conditions such as usurious increase upon late payment or requiring commercial insurance."