If you're not watching live TV, you don't need a TV license. If you start receiving threatening letters from the licensing companies simply ignore them, you are acting well within the law not paying your license fee providing you're not watching live TV. BBC iPlayer and other on-demand TV such as Netflix is fine to use. If you get a knock at the door asking to come in so they can check if you're watching TV just refuse to let them in, they have no right to enter your property without permission.