You need to provide a whole lot more information in order to even guess at the answer!
Are you:
Drawing, knife cutting, 3d printing, cutting wood, cutting aluminum, cutting steel?
Ball screw, belt drive, acme screw, acme with anti-backlash?
Air bearing, ball slides, wheels, plastic bearings, metal on metal?
Plastic frame, aluminum frame, steel frame, cast iron frame?
Slow, faster, very fast, extremely fast?
Wood accuracy, metal accuracy, extreme accuracy?
On a tight budget, have money, price is no object?
I ordered the questions by increasing cost or difficulty from left to right.