Is this a 1660 Super or normal 1660? What Motherboard is it? What PSU, Im assuming Corsair CXM or CX
Be specific on what parts are in the computer. Also if this is indeed a non Super 1660, then 750 is too much as you can build a comparable system with a 1660 Super which is 10-20% faster then the 1660 for about 700 USD and that includes a 1TB NVME SSD.
CPU: AMD Ryzen 5 2600 3.4 GHz 6-Core Processor ($117.76 @ Amazon)
Motherboard: MSI B450M PRO-M2 MAX Micro ATX AM4 Motherboard ($74.97 @ Amazon)
Memory: G.Skill Ripjaws V Series 16 GB (2 x 8 GB) DDR4-3200 Memory ($69.99 @ Newegg)
Storage: Crucial P1 1 TB M.2-2280 NVME Solid State Drive ($112.99 @ Newegg)
Video Card: EVGA GeForce GTX 1660 Super 6 GB SC ULTRA GAMING Video Card ($228.98 @ Newegg)
Case: Phanteks P300 ATX Mid Tower Case ($49.99 @ Newegg)
Power Supply: Corsair CX (2017) 550 W 80+ Bronze Certified ATX Power Supply ($51.98 @ Newegg)
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2020-02-17 22:08 EST-0500
I would try also to sell it on eBay as well as Facebook Marketplace. Your price is good if it is indeed a 1660 Super, but as I said be more specific with parts. Also the high quality parts line is a red flag for alot of buyers, especially since theres no specific mobo or PSU make and model listed. Again if this is a Corsair CX or CXM PSU, although a good budget PSU I wouldn't say its high quality.