If you’re looking to sell CDs online, there is no shortage of options- in this video, I spent a little time talking about the 5 that I have personally used.
If you’re looking for the most bang for your bucks, ebay or amazon is your best option, but if you’re more concerned with time and turnaround, decluttr or FYE is probably a better bet.
Discogs is good for the casual seller who is more concerned with a community and a place they can show off their collection.
My (and Cheapest) Barcode Scanner http://amzn.to/2j5DFAL
My Iphone External Mic ($25) http://amzn.to/2B0J986