floor tiles can vary. if you want basic ceramic tiles, figure about $3-6 dollars per square foot (including installation).
then go to those sanitary ware shops, get some prices for your fittings. add on about 10-20% for installation.
add that to the cost of ceramic tiles.
to this- add about say $200-300 for stripping out your existing fixtures and fittings.
then add about 10-15% for profit & overheads.
that should give you a rough ballpark figure.
i suggest you get a few quotes. but dont necessarily go with the cheapest one. also, as what i did with my own bathroom, its cheaper to source your own tiles and fittings and just pay the contractor for installation, rather than going to those all in one shops that you see all over the place.