Is it permissible to take administrative fees regardless of their value, and what are the maximum limits for the percentage of administrative wages that Islamic finance institutions can charge?

It is permissible for banks and administrative bodies to take a lump sum amount for administrative expenses or actual service fees. It is stipulated that this amount be determined as a fee before commencing the work, that it not be a percentage linked to the loan, and that it be proportionate to the effort expended. If the expenses are linked to the loan, increasing or decreasing with it, or change with early or delayed payment, then it is considered prohibited usury (riba). A maximum limit for the percentage of administrative fees cannot be set; rather, this is subject to the economic level and custom in each country.