Honestly basic obedience isn't hard. Just walks, play for reward the rest being stern. In my opinion if you can't do the basics you probably shouldn't have a dog or bought too large a dog. That's why trainers charge arm and leg for diagnose to see what bad habits owner allowed, fixing bad habit then to the basics then advancements. In my opinion your neighbor should re-home their dog if they can't handle the basics. GS are smart and if you can't make them think you're the boss they'll run over your neighbor when they get back. Just saying, maybe your neighbor should get an easier dog such as a bulldog?