Just finishing up a lovely little coop -- live in an urban area with lots of squirrels and raccoons. Hasps on all the doors but we aren't sure what to lock them with -- hasps are those hinged locking plates that allow a gate or door to be padlocked. We want easy entry but want to keep the chickens as safe as possible. Can a raccoon open a carabiner? Should we just close them with some twisted wire? Other ideas?