To go across the lake to fish, buy a used boat in good condition. Don't worry too much about brand, but more about condition. 10 hp 4-stroke should be plenty, but it depends on the boat's weight and design. Observe the boat builder's recommendation.
"There's more to optics than meets the eye."--anon
"...most of us would be better off losing half a pound around the waist than half a pound on our rifle."--dhg
