It is the only known surviving Apple-1 documented as being sold directly by Steve Jobs to an individual from his parents’ garage in 1976. And there is speculation that it could be sold for $1m (£626,904) at auction next month. Auctioneers Christie’s have put a guide price of $400,000-600,000 on the computer – although another Apple-1 reportedly sold for $905,000 last month. The latest Apple-1 up for sale is also operational, one of a handful thought to survive, and has a fascinating story…