ctm/supratours bus

i wonder how much is the actual price for the trip merzouga-marrakech or vice-versa with one of these two companies... i've tried to seach on onfc website and contact them via email but could't get a answer from them.

is it also possible/or frequent to get a grand taxis from merzouga to marrakech? how much would it cost?... we are 4 people.