Take $200 off the DuroMax XP4400EH 7 HP Dual Fuel Propane/Gas Powered Portable Electric Start Generator, dropping the price down to $499.99 + Free Shipping at Amazon. This is the lowest price out there by at least $150.

The generator has received some incredibly high marks at Amazon, earning a 4.5/5 stars from customers. The generator is designed to run on gasoline or propane, and has an 8-hour run time.