Coles has Garnier Olia Hair Colour 2P Platinum Black on special for $8.50, half its usual shelf price of $17.00, so you're saving $8.50 right now. Woolies is also running it on special at $6.60 (down from $11.00) if that's closer to home. Olia uses a no-ammonia, 60% oil-based formula that covers greys fully and skips the harsh smell you get with a lot of at-home dyes. At these prices you're paying less than a fraction of a salon visit for the same intense, cool platinum-black result.