We have a newish Merc and paid for the "Star Guard" paint and upholstery protection because we were very impressed with the way the same stuff performed on the previous Merc.
With the treatment comes as pack of various cleaning chemicals, including a Bird Lime neutraliser/cleaner. It is VERY effective, we keep it in the boot together with a pack of "wet one" baby wipes.
the only downside is that it is essential to re-apply polish after removing the bird poo, as has been said polish is your best friend.
The same stuff is available,
THIS is one source.
We had, some years ago, a black Merc. We were away from the car all day and the poo had set hard. It wasn't until the following day that we could get it off, but by then the poo on the boot top on a hot day ate through the clear coat and into the paint, in the end a re-spray was the only cure.
Although bird poo may appear to dry it is still acidic and will keep doing damage...it is vital to get it off as fast as possible, especially in the summer when heat makes the acid reaction go much faster!
