The smartwatch market feels like it's petering out, but that doesn't mean that there aren't some good options to be had. One of the best out there is Samsung's Gear S3, which represents an alternative competitor to Android Wear. You can grab the Bluetooth-only Frontier version for $239.99 over on eBay. Even though it's open-box, you're still saving $110 off of a brand new smartwatch.
The Gear S3 sports a 1.3" AMOLED screen, a rotating bezel for navigation, an Exynos 7720 SoC, 768MB of RAM, and 4GB of storage. You also get full Samsung Pay support, including the MST-compatibility. GPS and IP68 come standard, though this particular model (R760) is lacking LTE. To top it all off, the 380mAh battery can go for quite a long time (I get about three days on my Gear S3 Classic).
The eBay seller, poppy9780, has a 99.7% satisfaction rating and a Top Seller badge. You get a 30-day return policy from them, too. So if you're in the market for a new smartwatch, this is definitely an option to consider.