Start with super straight and flat wall studs and the $$ premium that that will require. Then the $$$ premium for the plasterer and the double layer of upgraded stock.

I always suggest having the same floor throughout. It gives it a more ample feeling, consistent and not disjointed. As far as the walls go for the bathrooms we become more creative with special and unique materials for each bathroom and in this case each bathroom has its own personality . J Design Group, Interior Designers Williams Island - Pinecrest - South Beach - Miami - Sunny Isles - Miami - Modern Interior Design Firm in Miami, Florida - Luxury Ocean Front Contemporary Decorators - http://www.JDesignGroup.com

you can go for vitrified Italian tiles

It totally depends upon your interior theme. Now a days polished cement floor is in as it gives quite a raw look and you can go for some combination of glass mosaics with it. Else you have so many options readily available in the market.