100% gotta be with the dog for at least a week or more (I've always done a couple and in the latter week maybe popped out for 10-20 minutes before returning), it creates a bond with the animal and also shows him/her who's 'master' of the house - youve gotta create a level of behavioural expectation immediately and be consistent in your commands and demands; this is easiest to do as early in their life as possible.

Plus, if they wake up and there's no-one about your house will be fucking ruined in minutes (I've never used an in-house cage/pen).

We’ve got 3 across 3 houses. I was worried when my parents got theirs, mine being 7 and him being there 2days 2nights a week when I’m working. He really took to the pup however and they’re like best pals. So much so I wish we had got another earlier! Can’t now as my mother would have 3x frenchies a few days a week and that’s a bit too much for her!