There's a deal on eBay at the moment which has a new, unlocked, dual-sim Galaxy S8+ at a bargain price of $630. The S8+ features a 6.2-inch SUPER AMOLED QHD display, Exynos 8895, 4 GB of RAM, and 64 GB of RAM, and a 3500 mAh battery.
https://www.notebookcheck.net/You-can-snag-a-Galaxy-S8-for-just-over-600.257786.0.html