Between business cards, flyers, posters, signs (lawn, car, and others), newspapers, people in costume dancing around, and other methods how does one decide what is right for them?

I've tried a lot of them, with business cards and flyers topping the list. Signs I have not had much luck with, giving minimal ROI. I'd like to find the person in the area that is posting signs, see what their ROI is like. Simple ones, 'cheap health insurance' with an 800 number.

Give the old...