insulation company

I want to use the govt rebate for insulation to boost up my property value. I want it properly done as i am planning to take it back as residency in the near future. Can someone recommend a reputable insulation company.

How is Marks group?
Er ... does insulating actually add value though?

I've never been interested in if a house is insulated or not, and REAs have never bothered asking me about it when I've sold a house.