Capacity to Contract:
The parties to the real estate lease contract must have the legal capacity to enter into the agreement. Age, mental competency and other issues are considered. A minor could not enter into a lease, thus this requirement would not be satisied and the lease would not be valid.
The purposes of the lease must be legal. If the property to be leased is to be used for illegal purposes, the lease would be invalid.
Offer and Acceptance:
All terms of the contract must be agreed upon by both parties. The owner or landlord would offer these terms to the tenant and the tenant would accept them, signified by their signatures to the lease.
Normally, consideration for a valid lease contract is in the form of rental payment(s). However, it could be in some other form, such as a trade of labor or property improvements for tenancy. Rent is normally fixed for the life of the lease, and cannot be changed unless agreed to in writing by both parties.