Amazon has the previous generation Apple MacBook Air 5th Generation Core i7 128GB 13.3" Laptop (2017 CTO model) for $800 with free shipping. This custom configuration ("Configure to Order") typically sells for over $1000.
Tip: Avoid low or no feedback sellers, search and select "Buy It Now" tab and sort by lowest price. You may modify min price to filter accessories to get MacBook Air auctions.