Cheapest and easy to use the LAN tester built with Wire Tracker 

LAN tester wire tester (model JW-360) is used not only to test network cable connections using RJ 45 connectors, but can also be used to find lost cables. This is the reason I have a LAN tester that has additional capabilities, a wire tracker. This tool is available on the market at a very affordable price, but nevertheless the LAN tester is still the cheapest.