I want some home fitness equipment but I can't figure out what to buy

 I want at home equipment and don't have that much money to go throwing around on a whole home gym. I think I should buy cardio equipment, but should I get a treadmill or elliptical? With the elliptical, sometimes your momentum may actually be keeping you moving but if you set the intensity at a good level then you can push and pull with your arms and get a great leg workout so that option seems like the least boring but if you use a treadmill then its all you. Then if you go with an elliptical do you do front driven: http://www.bayoufitness.com/Endurance-E5-Electronic-Elliptical-by-Body-Solid-256 or rear driven: http://www.bayoufitness.com/Detail.bok?no=160 (the prices are significantly lower for rear driven...maybe thats bad?) or center driven: http://www.bayoufitness.com/Ironman-Achiever-Dual-Action-Elliptical-Trainer-251
There are too many different options so I am lost!!