The still-new Galaxy S8 is arguably the best phone on the market right now. The gorgeous Infinity Display and Snapdragon 835 are features that competitors just can't match. That being said, at $756 + tax for the Verizon model, it's on the higher end of the market. Even though it's been less than a week since pre-orders have been arriving on tech enthusiasts' doorsteps, you can save a pretty significant chunk of change by purchasing one from a Top Rated Plus seller on eBay.
In case you've somehow already forgotten, the S8 sports a 5.8" 18.5:9 1440p AMOLED display, a Snapdragon 835, 4GB of RAM, 64GB of storage with microSD expansion, a 12MP camera, and a 3000mAh battery. There's also an iris scanner, fast wireless charging, IP68 water and dust resistance, and USB Type-C on board.
For $699.99, you'd be hard-pressed to find a better phone. Keep in mind that while it only looks like a $56 discount on paper, you're also saving on tax (and shipping) here. Since this is a Verizon device (with no Verizon branding!), you'll have no issue using it on GSM carriers like T-Mobile and AT&T. Plus, since all US variants are now designated SM-G950U, it's fairly likely that it may be reflashable to different firmware given how that worked out with the S7.
If you're interested, don't wait up. Maple Gold and Orchid Gray are already out of stock, which leaves Midnight Black and Arctic Silver. eBay says there's a "limited quantity available" and that 105 units have been sold in the past 24 hours. Check the source link for the listing.