Where should a dog sleep?

[KeepSmiling83]

We are thinking about getting a dog and have been looking at all the practicalities. I want to start as we mean to go on so was thinking of putting a crate (then a bed once older) in our bedroom. I don't necessarily what them sleeping in our bed but like the idea of them being in the room with us.

However lots of people tell me I should keep the dog downstairs otherwise they will get too attached to me and will develop separation anxiety. Eventually the dog would be left for 3-4 hours in the morning while I'm at work so I want it to build up to being alone. I don't want to make this more difficult for them.

Would I be making it harder for them by having them sleep in my room then expecting them to spend the morning alone? What do most people do and what has your experience been?

He sleeps in a doughnut bed in the hallway.
In the day time he sleeps in the sitting room.
When we go out he sleeps in the kitchen (otherwise he would sit by the patio doors in sitting room barking at pigeons).
He follows our routine and quite often anticipates what we are doing next and puts himself in the right place.