Looking to get into selling high-end sneakers...

A friend and I are looking for a little help. We're both at University together and looking to start-up some form of sneaker business where we purchase rare, high end, limited edition sneakers i.e. Yeezy Boosts... We are wondering if anybody knows of anywhere in particular that we could source the sneakers from initially? (Baring in mind we're UK based). Thanks guys.