Knowing the amount of the item being paid in advance at the time of contracting
This contract is invalid, because it is a Salam sale (sale with advance payment) which does not meet its necessary conditions of
knowing the amount of the item being paid to in advance (to be delivered later) at the time of contracting as well as other conditions. (Part No. 14; Page No. 107) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.