It kept me awake at night wondering, so though i'd report my costs here, might help someone.
Country Vic - cement sheeting on interior walls, quoted at $20 m2, so 40m2 + compliance certificate was $1800. Not bad for someone's 1/2 day work, though illegal for me to do as too large a volume. They removed, vacuumed, pvc sprayed that walls. All good. Very happy.
Previously I removed myself, (was the first time- very stressful ) costs included respirator $40, suit $20, plastic sheeting$80, trailer , dump - $40, but would add a crap load of stress, and very happy to get professionals for all major jobs.
Only my experience, but it might be useful for someone somewhere..