I guess this does seem an okay quote. If you are getting painting done, i am presuming that about 5k of this is for painting (incl supply). As a comparison.. when we got our house 8 weeks ago, we went to remove the wallpaper and found out that the plasterboard throughout the house was the wrong way around. We then had to remove all plasterboard from walls and ceilings and got new stuff put up. We got a skim over it all.. since its new plasterboard, thats waht was recommended. The whole job took about 2 weeks. If you need to get a second opinion before you go ahead, I can give you the number of the guys we used. Would highly recommend them. We got this all done for 7.2k, 1300 sq ft house. That is probably a bit more than we could of got it for, however, we decided to insulate internal external walls and put good insulation in the walls between rooms to sound proof it better. best of luck!