How much can my landlord raise the rent, and what is Ejari?

Ejari is the mandatory system for registering tenancy contracts with RERA; an unregistered lease gives you weaker legal protection. Rent increases are governed by the RERA rental index calculator on a sliding scale: 0% if your rent is near market, rising to a maximum 20% only when it is more than 40% below market. Landlords must give 90 days' written notice before renewal.