Apple products usually aren't this heavily discounted, but you can score a big discount if you buy used or refurbished.

Apple ME087LL/A iMac 21.5″ AIO Desktop, Intel Core i5-4570S Quad-Core 2.9GHz, NVIDIA GT 750M 1GB, 1TB SATA, macOS 10.8

Mountain Lion (Certified Refurbished)

$699.99 $1199.99

This Certified Refurbished product is manufacturer refurbished, shows limited or no wear, and includes all original accessories plus a 1 Year Apple Warranty.
Processor: Intel Core i5-5675R 3.10 GHz (Turbo up to 3.6 GHz) 4MB Cache, Quad Core
Screen Size: 21.5″, Resolution 4096 x 3204
Display Type: Retina 4K display with IPS technology
Graphics: Intel Iris Pro Graphics 6200
Memory & Hard Drive: 8GB of 1867MHz LPDDR3 (on-board, not upgradable), 1TB (5400-rpm) hard drive
Optical Drive: None

Wireless, Bluetooth 4.0 Wireless Technology, Integrated Audio, Built-in FaceTime HD Camera, SDXC Card Slot, Dual Microphones
macOS 10.11 El Capitan