I agree with Karlin,
I left my two when they were just over one year old. They are only ever left for a short time as I am usually home most of the time. I love my dogs and would always make sure they were safe all times. They always come first and they mean the world to me. They have the run of the house with all bedrooms closed everywhere is tiled so if they were to have an accident it would be easily delt with, not that they ever have. We have a doggy door out into the garden so they can go out when they need to, and they do use it. Most times they are just cuddled up asleep when I get back. It's SO sweet to see them like that. They have been really good so far never chewed a thing apart from the grass outside! Lol.
I think having the two has been good as they have been good company for each other. I always make sure they cannot get into ANYTHING while I am out. Like I said my dogs mean the world to me and I make sure they are safe always.
I made the mistake of giving Murphy the run of the house at about 9 months. It caused so many problems. He started pooping in the hall and peed on our bed. He also chewed the bed frame. We had to start house training all over again. It was just too much, too soon for him. We give him the run of the house now with his sidekick, they are normally asleep on the couch when I pull up.
I think Murphy was nearly a year and a half before we trusted him on his own
i have always given my dogs free run of the house as soon as i feel they are completely potty trained and reliable (usually 8-9 months). i normally close off the bedrooms and just let them run about in the other areas. experience (and hours of videotaped dog footage) has shown me that my dogs just sleep in their own beds while i'm out. we've never had issues with destruction, chewing or coming home to messes and i'm gone daily for 8 hours or more