Hi Guys. My parents want to sell there 21.5" 2011 iMac as they don't use it anymore. Main questions are, is it ok to sell it with the latest version of MacOS or does it need to go back to the OS that it shipped with, which in this case is OSX Lion? Reason I ask is, im not sure if you download the latest OS from the Mac App Store as to whether its still linked to your Apple ID or not? And we cant seem to find the original install discs so if that was the case it would be a little difficult. 2. Whats the best way to wipe the HDD and leaving it ready for the new owner? 3. How much would be a respectable asking price (£) for this model. Specs: 2.5Ghz Quad Core Intel i5 500GB HDD 8GB RAM Magic Keyboard And Mouse Original Box Good condition Thanks for any help received.