How much do you think this system is worth?

Tower: Dell Optiplex 7010 MT
Motherboard: Dell Optiplex 0GY6Y8
Processor: Intel Core i7-3770K
Memory: Corsair Vengeance DDR3 1600 4x8 GB (32 GB)
Graphics: PNY Nvidia GeForce GTX 1050 Ti OC 4GB
SATA_0: Kingston A400 120 GB SSD
SATA_2: Western Digital Blue WD10EZEX 1TB
Power: CoolerMaster Elite V3 400W

Question of the day: How much do you think this system should sell for? (USD)

Notes:
1. I added Arctic Silver thermal paste
2. The entire system has been completely cleaned, including underneath the motherboard
3. Windows is on the SSD, but is unactivated (user completes setup)
4. Motherboard BIOS is up to date.
 
Thanks, and no it does not include a key. I installed Windows to it using Rufus, completed the initial setup and turned it off. So the user has to activate windows, or let it stay un-activated until they get sick of the watermark lol

And I did some research on those parts, at a used rate it came up to about $530. To be honest, I forgot I made this thread. Thank you for your responses though!