[HELP] How to get dog to stop barking at everything?

So I have an awesome 4 year old mixed breed dog. He is a pit, basenji, dachshund, boxer mix. We currently live in a home and his barking isn't a big deal because no neighbors to hear him.This will change in 3 weeks when we move into an apartment. We don't want to have to get rid of him so we need to figure out right away how to stop his barking. He doesn't bark at much when we are home or even away from home. Just when someone is passing/walking passed our home or comes up to our door.So I need to train him and figure this out now. Please provide all the tips you can!!!Thank you!! via /r/dogs http://ift.tt/2rJRZD3