From personal experience, if you can in your area, ditch em. There's a bunch of banks and brokers who will not require a permanent phone if you have a physical address or similar. As long as you can prove habitation and/or that you're a real person, there's almost no justification. Mine's fine with me rarely even having a functional phone (I top up pre-pays only when I need them. Most months nobody I care about directly calls me.)