It all depends which way he/she wishes to be paid, if its a time consuming job then they could decide to charge you by day rate which is usually between £150 to £175 a day (tradesman)
Or they could decide to charge you by the area needed to be tiled, bare in mind some small jobs can be quite fiddly & time consuming (lots of cuts) which could cost more, so under those circumstances examples of cost per m2 would not apply.
The following prices are for labour with adhesive and grout included. You will provide the tiles.
Fixing 100mm x any size tiles £35/m2
Fixing 150mm x any size tiles £35/m2
Fixing 200mm x any size tiles £30/m2
Fixing 300mm x any size tiles £25/m2
Fixing 400mm x any size tiles £25/m2
Fixing 600mm x any size tiles £25/m2
Marble, Granite, Porcelain, Natural Stone or Slate Tiles
Fixing 100mm x any size tiles £50/m2
Fixing 150mm x any size tiles £47/m2
Fixing 200mm x any size tiles £45/m2
Fixing 300mm x any size tiles £45/m2
Fixing between 400mm to 600mm x any size tiles £45/m2
Mosaic Tiles can cost a bit more
Fixing 25mm x 25 mm mesh back mosaic tiles £50/m2
These are all just examples, but I hope it helps.
MC Home Improvements