Inside windows trim

[Chuck K]

Replacing windows and the company replacing the windows won't do anything about the inside window trim, they've already started so I can't go somewhere else. My question is (I have 20 windows) what should I expect to pay to hire someone to do the trim, is there a good place to buy the trim or let the contractor handle it? Finally, is this a DIY type of project, I have a couple of weeks to get things finished?