Vesper- Welcome to BYC. Much of what this forum is about is helping new chicken owners learn from our mistakes so they don't have to suffer the losses that result. If its just a latch problem, hopefully its a quick fix. A big problem is that coons are just about as nimble as people are so many of us have had to resort to using actual locks to prevent their entry. I'm sorry about your friends experience, but it is possible to predator proof a pen, its hard that the learning curve tends to be fatal to the chickens. Aside from that they are cute, I know very little about the eglu coops. If the run doesn't have a bottom , put an apron around the perimeter- a lesson I learned the hard way. Even if they can't actually get into the run from the ground, they can reach under and pull a leg out & eat it, leaving you with a one legged chicken or a dead one. Please let us know how you like your eglu and if it needed work to make it predator proof. It will help another person some time.
With bears, the only solution I've heard that works is running an electric wire/s/ around your yard to keep the bears out of the vicinity of the coop. There may be others. In my area, the other side of the size predator is a problem. Weasels can squeeze through incredibly small holes.