This DuroStar 4,000 Watt Gas Powered Portable Generator (model #DS4000S) drops from $479.99 to $249.99 at Amazon. Plus, shipping is free. With the exception of one seller on eBay (which has it for the same price), this is the lowest price we could find for this model by $50, with other big box retailers selling it for $300-$380. It features a 4-gallon gas tank with an 8-hour run time, two 20-amp outlets and more. Note that this item cannot be shipped to California. Sales tax is charged in most states.