V.W.
The only tip I have is that you probably WILL want a treadmill mat. We had a treadmill years ago (one of the NordicTrack ones with the arm things) and where the actual wrap around tread goes around the machine (the belt) it can leave a powdery greasy dust. I know that sounds like they are mutually exclusive, but they aren't. And it is hard to clean. The mat helps catch that, and also can help avoid the deep imprints from the "feet" into your carpet, or scratches to your floor if it isn't carpet.
Eventually, even if you get rid of the treadmill one day, you can use the mat for other things. Like resting dumbbells on them. Or underneath a yoga mat or whatever.