We as human beings love to seek out deals. It's fun and exciting. I personally feel a sense of victory when I go to a local store like Target or Bath and Body Works and find a candle which was full price just a few months earlier for half off. Deals like that are GREAT!
However, picking a quality treadmill does not work like that. There are many things to factor in when being a treadmill. Runners world published a great article discussing just that: The Trouble With Buying Cheap Treadmills.