I think worries about our dogs can be much like with our children - and I don't like comparing one to the other.
When my kids were little I wanted to know they were well mannered when at friends houses. The reports back were always good. Lots of "please" and "thank you" were offered at the appropriate times. They were polite and respectful.
Good to know because with little ones, you can never be 100% sure when they are not at home. God help the mom if she put anything foreign on the KD or didn’t cut the crust off the grilled cheese ☺
I have done and continue to do a lot of management with my 2 dogs for various reasons. It's second nature for me at this point.

This past weekend was a busy one for me and I was out of the house for much of it and relied on friends and neighbours to tend to my dogs. Beardie doesn't do well with change so I of course expect, people coming into the house would be a bit odd and perhaps unsettling for him. 
I gave the necessary precautions regarding resource guarding and meal times. Beardie doesn't always eat right away and will walk away from a full bowl of raw meat. This can be tricky if Westie decides to investigate the bowl before it's empty. Which they both do once they are both finished.
 I always let them out for pee breaks individually as Beardie gets great joy out of peeing right on top of Westie as he goes. At the very least Beardie follows Westie around and I feel he should be allowed to pee in peace!
Once the little one has gone I let the big guy out and he, of course finds the spot and goes right there.
I had visions of coming home to a yellow Westie ☺
The report from those who tended to them - they were wonderful! Well behaved, no issues.
We get caught up (at least I do) in what we see and expect to see. 
It's good to get fresh eyes to look in on life sometimes.