Another and less invasive option would be modular furniture, a modern twist on the back-to-wall design.
A more economical alternative, modular furniture tends to be wall hung, giving a floating effect, whereby a singular sloping vanity basin unit will be fitted alongside a separate, but matching, storage cupboard.
Although free standing modular units are available, the idea of a wall hung design is to open the visible floor space giving the illusion that the room is bigger than it actually is.
As with all furniture and storage options modular furniture comes in a wide selection of colours, shapes and sizes.
Some designs even lend themselves perfectly to overly small spaces in the form of corner units however considerations on whether incorporating furniture into such a space would increase risk need to be accessed.