Advantage 1 - Americans knew the terrain, whereas generally the British did not. General Howe actually did know the terrain since he was on continent fighting against the French and the Indians...
The British were fighting for money and pride. The Americans were fighting for their freedom and homes. Sure, we ran a lot and got the French to fight, but that's part of our charm. At least back...
They were fighting on their home turf so supplies and instructions didn't have to travel 3000 miles like it did for the British. They had support from the French (ahs)