4GB of RAM
OS X v10.11 or later
Minimum 6GB of disk space. Up to 51GB of optional content available via in-app download.

Best prices are on iMacs in the 2010 or 2011 era. They are the least expensive. Get one with an i5 or i7 processor and at least 16 gb of ram. I feel they are great machines when working with music. I have used them for a long time without a problem.