Ideally, you want to make sure to have copies of your rental contract in both English and Arabic. The contract should cover all the important details, including rent and who is responsible for paying for repairs.
Make sure your contract is clear on the terms of the lease (length, conditions for renewal, monthly rent). Insist that once these items are finalized, they are non-negotiable. You may find it helpful to have an Egyptian friend (or at least an expat friend who speaks solid Arabic) with you during this process.
A printable copy of a lease contract is available here for download.