Where I live, until recently, I had to park my car outside in an uncovered parking spot. My car was right next to a tree and a huge climbing vine that ran up the side of a building. Very quickly I noticed bird $%*# showing up after only a day or two. I realized a car cover would be a lot cheaper than washing my car at the carwash every week.
I went online to SealSkinCovers.com and found the exact size for my vehicle make and model. I was surprised to see they were running a special and managed to get a cover that protected against all weather conditions and of course bird poo.