Fitting a back to wall toilet

[sophiejazz]

I'm about to have fitted a back to wall toilet and am wondering how I should box in for access. The whole bathroom is to be tiled. Any tips please?
Also, the chrome flush button is relatively small, anyone know of where I'd get a fancy replacement?

Many thanks

 

[ChrisR]

Have a panel supporting the tiles removable. Same size as a square of 6, or whatever, tiles. Then just use silicone to go round the 6 tiles in place of grout. Then a knife releases the panel if necessary.
If you grout it in, it makes a hard job to remove it.

Buttons and mechanisms are all different. They're usually a pair with the flush valve so you might have to replace the set, though better makes have options.