It is best to have the written agreement signed personally by the landlord and the tenant. It can be the case that the landlord promises certain provisions verbally, only to reverse them later in the written contract. The written contract or agreement is legally binding. It is also advisable to engage a good property lawyer to look into the contract before signing.
The typical lease term for condominiums, apartments and houses is one year. If the tenant will only be living in the Philippines for a few months, it is best to rent a serviced apartment.