Looking for an apartment to rent? Know your rights before you sign a lease.Landlords and property managers in Massachusetts use a legal document known as the rental application to evaluate prospective renters effectively. You should fill out the Massachusetts apartment lease once you are ready to sign a lease contract. A Massachusetts rental agreement can be one of two types. The difference is whether landlord and tenant are obligated to stay to one another. Learn what to include in a Massachusetts rental application form. Use an online rental application template on Avail. Leases are legal agreements that explain your rights and responsibilities as a tenant, as well as your landlord's responsibilities. A Massachusetts rental agreement is a formal contractual agreement between landlords and tenants for leasing a property in the state.