Boat cleaning services

Boy the things you discover during a school run. Last week it was the sight of a coffee van that caught my attention. Yesterday in the morning we were behind a van and I noticed that it was a... boat cleaning company. Call me silly, but I didn't know there was such a thing. I thought boat owners cleaned their bot themselves. But hey, it makes sense that some don't. After all, there's car wash, so why not boat wash? We are relatively near the Thames, so there must be plenty of occasions round here for this van to do business. But it's the very first time I have seen a boat cleaning service.