Sublet means to rent an owned property to another person and that person leases out to some another person. A formal approval of the landlord is required in this case. After subletting, the existing tenant becomes the landlord of the new tenant. A written agreement has to be made between the landlord and the tenant. The agreement points out that the particular property is being let out to that person in exchange on monthly rent and deposit. A lump sum deposit has to be paid as a security which is refunded back when you leave the property. The monthly rent is decided by the landlord which is calculated upon the region and area of the property.