Let us buy your old used office phones for cash. If you have used phones or old phones that are out of service business telephone equipment, please CONTACT US so that we can bid for and buy your telephone equipment. We buy office phone systems in all quantities and our parent company sells phones.Comtech sells both Brand New and Fully Refurbished Phone Equipment.We buy and sell phones that are out of service and we buy and sell business phone systems.e buy office phone systems in all quantities and our parent company sells phones. Comtech sells both Brand New and Fully Refurbished Phone Equipment. We buy and sell phones that are out of service and we buy and sell business phone systems.