Hello there, I am going to do a clean install on my family's(now mainly my sisters/nephew's comp) 2010 27" iMac. It's been having a lot of problems because of icloud and keychain inconsistencies and it's clogged up with legacy apps and files from our 2007-ish iMac. So we've backed it up and I'm ready to wipe and reinstall the OS. I'm going to make a USB boot drive with that OS version so I need that .app or whatever it is to do so. I was planning on going back a couple OS' to Lion or Mountain Lion to better support the hardware and such. Though, are there better reasons to install Mavericks on it? I don't think Yosemite or Capitan would be worth it. My problem is, I don't have a Lion install disk or USB and I cannot get access to it on the App store anymore. Does anyone know a good source or site for Mac OSX install packages that are free downloads? I don't want to pay Apple $20 for a Lion install USB.. EDIT/Update: I ended up wiping the main drive partition and creating a new OS install over it using the Command+R boot drive utility. It's re-downloading Mavericks(what it's been using) so hopefully after it's installed that and created the admin account it should work a bit more smoothly.