Animating workers

I am producing an animation of some workers in a construction scene for the background of a website. It will be produced in flash and exported to video so animations will need to be produced in the timeline. The main thing I'm looking for is the people to do some nice realistic movements, the rest I can do myself. The guy with the ladder in that image could maybe lower it into the screen, climb down it, then pick it up and walk off the page. The guys in the hole could walk in, open it up, climb in and close it again. The guy on the rope could either descend and walk off, or walk in and ascend. The purpose is to use as the background of a website so the whole animation should be no longer than 15 seconds. Here is a visual for reference: [login to view URL]