Squirrels entering through broken cornice

Hi Everyone, thanks for your help on my last question.
Our new problem: part of our cornice blew off in Hurricane Sandy. Our handyman nailed it back on, but now squirrels have worked their way thru an open spot and are now in our tiny crawl space–I can hear them up there. The problem is, there’s no easy access to this space–it’s maybe a foot tall, so you can’t even crawl there. We need to repair the cornice, but don’t want to do so and trap squirrels inside, for humane and smell reasons. Any ideas? I called my exterminator and he said he couldn’t really help if he couldn’t get in there. I think we really need a contractor who repairs cornices. Does anyone have a good person? We don’t want a fancy expensive job. Thanks very much.