In reply to Cliffm:
I have just bought my daughter some climbing holds for christmas , i got her a pack of 10 mini jugs for about £30 i am going to mount them on a piece of 24mm ply ( with extra holes in for versatility) and then use heavy duty bolts to bolt that to the wall
that way i can have 30ish holes for arranging the holds but still only have 4 or 6 holes in my wall.
bought the holds from Mock Rock