The size is in a foreign notation, so I wrote 23.5, but please research the details yourself. The size is small, and I've only worn them once. The only dirt is on the soles, which I washed lightly. I only washed them lightly because I thought scrubbing them would cause damage. The dirt is only on the soles. Otherwise, there's nothing in particular. I applied waterproof spray before use, so they are water-repellent. They are also easy to clean when dirty. I have worn them once, so I will have to decline if you dislike used shoes.