Dell sell their reconditioned units through Graysonline.
I picked up an Inspiron 7520 for $600 delivered, i7, 8GB ram, 1TB hard disk etc. I also bought a Latitude E6520 for a friend for $500 delivered, i7, 8GB ram, 750GB hard disk etc. You can buy limited warranties for the reconditioned units, but my attitude is if they are not dead on arrival you will generally be fine. Neither of these units has missed a beat. May be another option for you to consider.