You don't have to write up a sublease contract. This booklet explains many of these laws you need to know and provides resources where you can find more information about landlord and tenant issues.The Easiest Way to Add e-Signatures. On or before the first day of the second month of the Lease Term and of each month thereafter, the installment of Base Rent and other sums. A sublease agreement is a legal document allowing existing tenants to rent out their rented space to another party, the subtenant. Dealt with any broker in the negotiation of this Agreement. If your property is in a special taxing district, you must include that. The sublease agreement will reference the master lease agreement between the existing tenant and the landlord.