Is it permissible, in Islamic law, to work in the field of media buying, which involves managing paid advertising campaigns on social media platforms, knowing that payment is made automatically and directly based on a pre-determined budget?

Purchasing advertising space (Media Buying) falls under the category of selling services or benefits. It is a lease contract (Ijara) whose validity requires the knowledge of both compensation elements: the rent (Ajr) and the benefit (Manfa'a), as it is a compensation in an exchange contract. The knowledge of the benefit is achieved by estimating the duration or the work. Therefore, if the rent and the extent of the benefit are known, and the ambiguity regarding them is removed, there is no objection to executing it automatically.