My backyard is 5.5 metres by 12 metres. (That is a length of 5.5 m and a width of 12 metres). I have poured a concrete slab in the top right corner where I have placed my shed which is 3 metres by 3 metres. I am also going to create a flower bed which will be half a metre from the fence on the left side and top end of the backyard; hugging the fence. I need to order buffalo grass to cover the rest of the space. How much square metres worth of Buffalo Grass will I need?

How much will it cost me considering that Bunnings sell Buffalo Grass for $14.20 per metre squared?