...except most switches can't cope with the current of anything but a small motor. The schematic with relays is a good start but doesn't really show the wiring; just the concept.
Chances are the switches for up/down can't either.
Combined with above leads to a very simple solution.
Put the limit switch inline with the corresponding control switch. The top limit switch in series with (after) the up button. Use SPDT or DPDT switches and wire them switches such that one cuts the power to the other, there by preventing them from be pressed at the same time.