I have never had a yard. Of course, I've never had a puppy, either. They also got walks EVERY day, LOTS of walks, and this was in a climate where winter is two feet of snow. And not pretty, Colorado snow that is all fluffy and white, angry East Coast USA grey sloggy snow.
The staffy was eight years old when we got her. The Akitas were about five years old each but never met each other or lived at the same time. The Bouvier was the most difficult by far, but he had been thoroughly abused as a puppy and was more energetic than the other three dogs put together, he was also only two years old when my parents got him.
These were houses w/ stairs, but no fenced yards.
At this point I am in a unit (no stairs) and have no dog. I'm still researching/figuring out what would be best and happiest. Looking at toy breeds mostly. I still like walking a lot and like the enforced gym membership aspect. And there's no snow! All-weather walking here is really painless for me in that sense. And I'm leaning towards an adult dog.