A mill, of the bed or knee type isn't going to be found in those kind of travels for that kind of price.
Travels large and square like that are usually found in something more like a router, or a gantry or bridge mill. Even a router is going to be tight in $1500.
What are you trying to cut, and what kind of cuts are you planning to make? Simpler 2D shapes, or complex 3D contours? What kind of material, foam, aluminum, stainless steel? The harder the material the more you need in a spindle, and that will cost a lot.
Desktop mills (just the mill, no electrics or computer) are generally going to have significantly smaller travels than listed. Just for reference, the bridgeport and machining center I use at work don't hit 24"x24", cost a lot more than $1500 each, and won't fit in the average house.