Abstract: Described herein are techniques for receiving, by a telecommunication service provider, used telecommunication devices from a plurality of subscribers of the telecommunication service provider. The used telecommunication devices may each have been purchased with an installment plan on which a balance is owed, and different balances may be owed on different ones of the used telecommunication devices. In exchange for the used telecommunication devices, the telecommunication service provider may pay off up to at least part of each of the balances. Further, prior to paying off the balances, the telecommunication service provider may obtain identifiers for the used telecommunication devices and verify that the obtained identifier for each used telecommunication device matches an identifier that is associated with one of the subscribers and is stored in a data store of the telecommunication service provider.