When the brickwork had been finished at our place (this is 3 years ago now) our builder advised me that if I wanted to I could go out to the house and salvage any/all of the unused bricks. He said all I needed to do was pile them up in the back corner of the block so they'd be left alone when the site clean was done. They were my bricks, according to him (as you specifically choose the bricks you want for your house and the builder has to buy them in pallets, any leftovers are not much use to the builder - he'd have to store them all (from each job) until he had another house/use for the same bricks - and then there's the risk of not being able to get any more of the same to match them), so I could choose to salvage them or leave them to be removed with the rest of the rubish.
I chose to salvage them. It took a few hours but I ended up with what looked like about 1.5 pallets of red/brown and .5 of a pallet of cream bricks - approx. 700 in total.
When I later (2 years later) decided to do all of the brickwork for my new outdoor area - BBQ, bench, raised garden beds, we had all of the bricks we needed (even down to having the right quantity of each colour

I recommend saving as many of YOUR bricks as you can...