Ok, it's six months old. Prong collar while training should be ok. But not for house-training.
Maybe the best thing, besides returning the puppy, would be to put a kennel up in the basement or garage. Get up and spend an hour with him in the morning before work. And I mean out walking him, working him, training him.
Then kennel him. plan on cleaning the kennel daily. It would be better to get him house trained first. and then let him out midday, and then as soon as you get home, that dog is tethered to you for the rest of the night, and you spend at least 2 hours doing something active with the dog, hiking one night, dog classes one night, playing tug/fetch one night, walking the bike path one night.
The rest of your evening really has to include the dog, and you will have to keep him close so you can rush him outside, and praise the pottying when he is outside.
It really does sound like the wrong type of dog for your situation, or at least, maybe the wrong age. If you got a dog that was alredy 3 or 4 years old, you could pend 45 minutes in the morning, and some time in the evening, and then let the dog roam around the house, and train on the week ends. But puppies need much more hands on, attention, play, training, etc.
Jenna, RN CGC & Babs, CD RA CGC HIC
Heidi, RA CGC
SG3 Odessa, SchH1, Kkl1, AD
Ninja, RN CGC & Milla, RN CGC
Joy, Star Puppy, RN CGC
Dolly CGC & Bear CGC