Always keep a spare bottle of water, rags, and spray wax in your trunk. The worst is when you get crap the size of pancakes on the convertible top. Yeah, if you leave bird sh** on your car, your paint will fade; usually takes 1 week if you don't have some good wax on there. Some bastard left droplets of ink all over my hood a few days ago, luckily I have so much wax on there, I was able to take it off with my emergency detailing arsenal.