I've had several quotes, some ridiculous, some reasonable.
Downstairs toilet, which must be no more than 2m x 1m and for which we only want the floor tiled and a small splashback i had two separate companies quote me about £4k which is just absolutely ridiculous, not going with either. The main bathroom, a much bigger space that is 3m x 3m and we're getting fully tiled, with shower over bath, bath filler, and sink with storage drawers underneath etc, skim ceiling, quotes came in at £9k to £13k. The £9k quote is what we went for as they were the most professional and it was our design and we chose some high end options (fancy mirror, bath filler, extra strength bath, rainfall shower etc). Some places are an absolute rip-off, had one place quote me £100 per square metre for a tile we liked, while the other place was doing it for £25.
However, the guy earlier in this thread.... £45k for a bathroom, got to be absolutely joking.