Factory Authorized Outlet via eBay offers the Duromax 3,850-watt Dual-Fuel Portable Generator, model no. XP4850EH, for $299.99 with free shipping. That's tied with last month's mention as the best price we've seen. (It's the best deal today by $175.) This generator runs on propane or gasoline and provides a constant 3,850 watts (4,850 watts peak) of power.