I do not like electrical collars/fences. My parents had a golden a while back, and after trying everything else with him, my dad installed an electrical fence--he didn't care--he took the pain for a second, and ran off anyway. We are buying a new house, and will be putting up a secure fence, and the dogs are left inside when we are not home. Crates are best for puppies, but when they learn the rules, sometimes they can have run of the house when no one is home.
I would also make sure you microchip or tatoo your dog, as well as have a license for him or her, and have pictures around all the time.
I'm sorry for your friend's dog--that is so sad.