Best Buy offers the AT&T DECT 6.0 4-Handset Expandable Cordless Phone System with Digital Answering System, model no. CL82401, for $49.99 with free shipping. That's the lowest total price we could find by $25 and the second-least expensive DECT 6.0 4-handset phone set we've seen. Sales tax is added where applicable. This phone uses DECT 6.0 (1.9GHz) technology, which reduces interference with 2.4GHz devices, like wireless networks. It also features a built-in answering machine, expandability up to 12 handsets, caller ID, speakerphone, and more.