yup 6000 sqf @ 10HKD/sqf = 60k. that's what i tried to say.
and dtb is right, such a price would include clearing of old paint, redoing the foundation, leveling out, water-sealing (if any), etc. i would think that one only does all this when doing a complete redecoration of the whole place (including possible some electrical and piping work that damages the outer wall layers)
i guess it's really the question what the OP has in mind. I would not be surprised if he didn't know exactly what he needed and the contractor simply quoted the highest possible, waiting for renegotiation