With the way Princess digs up her water like a maniac I think she'd love a little pool.
I just have a small balcony so I think I'm actually buying an under the bed storage container.
It's a good size & shallow enough to get in & out of. It'll also be easy to fill as I don't have a hose, yet wont be too heavy to empty, etc.
I've been looking for a pool for a long time with no luck.