Hi RickinIA,
I saw your post about the Sole F80. If you are looking at sole please also look at Spirit. A chinese manufacturer by the name of Dyaco makes both of these brands. However, for roughly the same price, you will get a much higher end product with the Spirit treadmill.
Sole is great at marketing but they do not use the smae high qulaity parts that are used in Spirits. Since your son weighs approx. 250 lbs, I would say to get the Spirit XT675 treadmill (which actually has a light commercial warranty). It also has a 10 years parts, 1 year labor warranty and should hold up with your son running on it. If you tell me what city you are in, I will try to refer you to someone. Just let me know.
Good luck getting fit. Thanks, Ray