Well,I only have the one male coachwhip and he's been happy in this homebuild viv/cage...size 110cm x 48cm x 46 cm.If I ever get the female I'm after I would house them in something larger so they have their own space,but not so big that they could'nt find eachother.
Look through the archives on this forum ...there are some great cages,including the one used by Bill (sighthunter),which allows the snake an outside area (very clever)...also look-up coachwhip on you-tube.

regards Paul (uk)