GreenMetropolis - second hand book seller/buyer

A flyer for GreenMetropolis came with our Woodland Trust magazine a few days ago and it's quite intriguing...

From their website:

Whether it's the latest release or last year's bestseller, all our books sell for one unbelievably low price of £3.75 and all standard paperbacks include FREE delivery. We also pay £3.00 for every book you sell with GreenMetropolis.com. Intrigued? Then read more....

By recycling used books not only are we saving existing trees, we're actually planting new ones. How? GreenMetropolis.com donates 5p for every book sold to the 'Tree For All' campaign run by the Woodland Trust.

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Basically you can buy any (secondhand) book in stock for £3.75 (and P & P is free on paperbacks). An alternative to amazon marketplace with its steep P & P but I'm not sure whether you get the same protection.