How much for 12m2 tiling?

600 x 600 square, normal tiles from builders range. We have already brought the tiles for $400 and have asked the builders tiler to tile our hallway. What do you think is the right price???

round $35persm2

Depends on how they do it and what materials they use, but I've been told about 60-70 / m2, but much more for small jobs. We've been quoted about $1550 for about 22 m2 (floor tiling, no screed).

I'd allow around $60/mtr for the 600x600.
However some tilers will charge a day rate on the smaller jobs rather than per mtr, so you might be charged around $500-$600 for the job seeing as it should be completed in the 1 day (unless he starts late in which case he may need to return to grout it in).
If it's porcelain then you could be charged $70-$80/mtr plus they'll have to screed the floor to ensure the levels are perfect
which would be an extra $5-10/mtr. Just be sure the tiler uses flexi glue- all new homes have a degree of movement so to allow for this you need to use the rubber base adhesive to prevent your tiles cracking with the cracks in the floor.
That will be an extra $20/bag but there are some tilers out there that will charge you the extra but then they use the cheap regular glue. Best to buy the glue yourself & ask the tiler to provide labour only.

Hope that helps
Suzy