I had a painting contractor paint the trim and baseboards throughout my home in October, 2002. He supposedly used an oil-based primer and oil-based paint (two coats) which I was told by the contractor would be more durable than latex. The paint now seems brittle or dry and chips off easily. Why is this happening and what can I do to fix or repair the problem? I noticed the contractor did little (almost no) sanding throughout the process and I wondered if this might have something to do with it's lack of staying power now. Also, could he have used the wrong type of primer or paint?