We paid a fortune for our water tank - it came with our house LOL! The house also has water efficient fittings throughout, so we also bought a water effecient washing machine and dishwasher. We also have 4 minute showers mostly - I have to admit that sometimes I go over (I'm using the courier mail timer), but other times I'm under so I figure it evens out. Also DH only takes 2 -3 mins so like a pp, I figure I can have the extra time!