Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Does it still have warranty?
For 530 USD it is a good deal, but maybe check www.mac2sell.net )often gives higher values, maybe deduct 100 USD or so from its recommended price) and eBay for prices on this model.
Also know, that can you upgrade to 16 GB RAM yourself, if you want or need to.
 
$530 USD sounds like a VERY good price for that, assuming everything is functioning as intended...
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.