A toilet can be refurbished using traditional toilet components, wash basins, cubicles, hand dryers etc. This can be done in a very basic way, with a simple re-tiling and some new cubicles, or in a more dramatic fashion with the interior of the toilet being refashioned and new entrances installed.
The basic rule is that as soon as you decide to knock down a wall, the costs begin to grow. We carry out refurbishments for Councils all over the UK, and see some which will work, and some which won't. Some basic rules:
Finally - consider charging. Is this toilet used by many visitors as opposed to rate paying locals? If so, you could look at door based coin entry systems or paddle gates.