What is the ruling on profiting from selling website spaces after purchasing the space from a third party, and is it permissible to receive payment for the space in advance?

It is permissible to buy or rent a space and sell it to another for a higher price for a known period, then rent it out again after the rental period expires at a price they agree upon. It is valid to collect the price before renting out the space if it is for renting a space and creating a specific design with precise specifications, and this is considered a form of "Ijara fi al-Dhimma" (lease with deferred delivery). However, with a specific name, there is an element of "gharar" (uncertainty/deception), because one might not be able to obtain the contracted-upon name. One can resort to a promise to lease (muwa'adah 'ala al-ijara) and take a sum of money from the prospective tenant to indicate their seriousness.