Macbook A1342 2010 - OS Installation Issue

I purchased a Macbook A1342 2010 (white one) from eBay and it arrived with software and a password on it. This was not in the seller's description. I instinctively (have had many macs before) used Disc Utility to wipe the disk and reinstall OS. All was going well until when I went to sign in before installation began it said: "This item is temporarily unavailable". I went on the internet in search of answers and someone suggested to use Online Recovery (which I did) and it reverted back to OSx Lion. The exact same error happened with Lion as it did with El Capitan right before it begins installing - "This item is temporarily unavailable". The Apple ID that I used has been used with Macs before but no older than El Capitan. I tried two Apple IDs which have both been used on Macs and both were refused. The seller is saying it is my fault despite him being the one that sold a locked product without stating so and eBay have ruled in his favour. How can I go about fixing this mess?

Thanks.

If you have access to the installer have you tried creating the bootable thumb drive from here?

Reading closer you don't have access to the installer. Running the online installer won't work because apple pulled the download links that it uses. I suspect this is thinly veiled attempt at pushing people to upgrade.

Check this out: https://diskmakerx.com. It will create the thumb drive for you. You will most likely have to go here and buy El Capitan from apple if you haven't installed already.

Its also worth checking out http://dosdude1.com/highsierra/ his tool will download the High Sierra installer for you from apple. This is the last supported release for your MacBook. Once you have the installer you can use DiskMakerX.