eBay with Bluetti has the certified refurbished BLUETTI 268Wh Portable Power Station (600W AC inverter) on sale for $148 - 20% off with coupon code SPRINGSAVE20 [Exp 3/17] = $118 with free shipping. Roughly 42 cents per Wh. Includes USB-C charging port. Includes 2-year Allstate warranty. 

• Seller notes: “Nearly New, comes with AC and Solar charging cables, 2 years warranty."