Hi Sandrajo. We try and manage work so that our two (Collie and Greyhound) aren't left too long home alone. It still makes me uneasy when we have to, be it for 3 hours or 10 minutes!
4 hours is my outside limit, especially as our Greyhound has quite specific toileting needs! She likes routine. Our Collie used to have terrible separation anxiety, so we had to manage that. He is now very good.
It does depend on the dog, but as long as it is fed, loved, walked and happy, no-one is going to punish you for having to live! I wouldn't leave my two outside, but they are pets, not guard/working dogs.
If only people with endless free time could keep dogs, think how many more would be in need of a home...
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