Your starting point is always the Apple Refurb store to check the price of the most similar refurb unit.
By elimination, your machine must be an i7 -- but it would be well to state that in your description
Originally released July 2010
27-inch LED-backlit glossy widescreen display
4GB memory
1TB hard drive
8x SuperDrive (DVD±R DL/DVD±RW/CD-RW)
ATI Radeon HD 5750 graphics with 1GB memory
Built-in iSight camera
1 year warranty, eligible for Applecare
$1,569.00 free shipping, tax applies
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