Walmart offers the California Air Tools Ultra Quiet 2-Gallon Air Compressor for $150.12. Choose in-store pickup to drop it to $103.64. That's the lowest price we could find by $56. This oil-free compressor features a steel tank, 1-horsepower motor, and 120 psi max output.

A close price: Amazon has it for $105.75 with free shipping.

Update: The price at Walmart has dropped to $101.57 with in-store pickup.