Urban residential rental in Colombia is governed by Law 820 of 2003. A well drafted lease protects both sides and prevents costly arguments later.
What it must not omit:
The parties and the property. Names and IDs of landlord and tenant, and a clear address and identification of the property handed over.
The rent and how it is paid. The monthly amount, the payment day, the method (deposit or transfer) and who receives it. Keep a record of every payment.
The term. The agreed duration. If none is agreed, the law assumes one year. Renewal and the notice required to end the lease should be in writing.
Guarantees. A co-signer or rental insurance policy is identified here. The law prohibits cash deposits or extra installments above the rent as a guarantee.
Utilities and administration. Who pays utilities and the community administration fee.
Condition of the property. A signed inventory or handover record avoids disputes when the property is returned.
This is general information, not legal advice. For your specific case, review the contract with a lawyer.