Brick slips

Hi I am wanting to brick slip my wall it has recently been sound proofed and plastered and I’ve read online I can’t do this on plastered wall, as it is too smooth and the brick slips will fall off. I’m due to have it painted on Wednesday and need to ask if I should be asking my painter to just mist coat, leave it plastered or paint it fully. Also how much would it be to installed brick slips on a wall that is 165x91 inches? Thanks