A new start-up based in New Jersey is offering people stuck in lengthy wireless contracts the opportunity to switch handsets without paying full price. Rentobile has bought cell phones from the major cellular carriers at full price, and then rents them to those interested in using a new handset even though they are in the middle of a contract. The company has between two and five handsets for each carrier, and rents them out at $20 to $50 per month, depending on the handset. Handsets can be rented for as long as a customer wishes, but Rentobile encourages customers to change handsets often.