How do I download an OS (Lion) for a used-IMac that's had a complete memory wipe?

Question

I just recently bought a used-Imac (only 5 months old) from a friend of mine which he did a complete memory wipe on the computer. Operating System and all. He had Mountain Lion which is the operating system the computer is asking me to reinstall but I can't because my apple I.D. never purchased Mountain Lion. He told me that he got it illegally which I didn't care too much for. I know the OS is only $20 which I would gladly pay for but the problem is that I have to have OS X v10.7 Lion to be able to download it. I tried downloading a version of it but it had said that I didn't have enough space on my disc for it? By the way, did I mention that nearly all memory was wiped away from the computer. I had 230-something gigabytes on my computer so this didn't make any sense to me as to why it couldn't download 10.7 Lion. Can anyone help me on this?

Answer 1

You only need Snow Leopard 10.6.8 in order to download Mountain Lion.
Upgrading to Snow Leopard
You can purchase Snow Leopard through the Apple Store: Mac OS X 10.6 Snow Leopard - Apple Store (U.S.). The price is $19.99 plus tax. You will be sent physical media by mail after placing your order.
After you install Snow Leopard you will have to download and install the Mac OS X 10.6.8 Update Combo v1.1 to update Snow Leopard to 10.6.8 and give you access to the App Store. Access to the App Store enables you to download Mountain Lion if your computer meets the requirements.
     Snow Leopard General Requirements
       1. Mac computer with an Intel processor
       2. 1GB of memory
       3. 5GB of available disk space
       4. DVD drive for installation
       5. Some features require a compatible Internet service provider;
           fees may apply.
       6. Some features require Apple’s iCloud services; fees and
           terms apply.
Upgrading to Mountain Lion
To upgrade to Mountain Lion you must have Snow Leopard 10.6.8 or Lion installed. Purchase and download Mountain Lion from the App Store. Sign in using your Apple ID. Mountain Lion is $19.99 plus tax. The file is quite large, over 4 GBs, so allow some time to download. It would be preferable to use Ethernet because it is nearly four times faster than wireless.
     OS X Mountain Lion - System Requirements
       Macs that can be upgraded to OS X Mountain Lion
         1. iMac (Mid 2007 or newer) - Model Identifier 7,1 or later
         2. MacBook (Late 2008 Aluminum, or Early 2009 or newer) - Model Identifier 5,1 or later
         3. MacBook Pro (Mid/Late 2007 or newer) - Model Identifier 3,1 or later
         4. MacBook Air (Late 2008 or newer) - Model Identifier 2,1 or later
         5. Mac mini (Early 2009 or newer) - Model Identifier 3,1 or later
         6. Mac Pro (Early 2008 or newer) - Model Identifier 3,1 or later
         7. Xserve (Early 2009) - Model Identifier 3,1 or later
To find the model identifier open System Profiler in the Utilities folder. It's displayed in the panel on the right.
     Are my applications compatible?
         See App Compatibility Table - RoaringApps.
     For a complete How-To introduction from Apple see Upgrade to OS X Mountain Lion.