Having trained dogs for obedience and conformation the most important thing is repeating over and over...when potty training, and they have an accident in the house, use a paper towel to clean it up, let them smell it, tell them no and then take them out and tell them to pee pee/or poop outside....usually takes me one weekend with this routine and they are good to go. As for nights if you don't have a crate I always just used the bathroom where an accident was easy to clean up. Put down a nice soft warm towel or baby blanket so their toenails don't get caught to sleep on.. the little plastic crate thingy from Walmart is a good idea, and the pet playpen is as well.A harness is best for small dogs, less trama and easy to just hook them up to take them out. Good luck and they are the lucky little babies to have found someone that will care and love them so much.