My friend and I had a very nice stay in Sophie's appartment. The location was quiet, with a supermarket right on the street and the next metro not too far away.
The appartment itself was quite small, but sufficient. It was also clean and tidy. Bathroom wasn't exactly polished, but definitely acceptable, no worries. Kitchen has everything to offer, so we cooked one night without any problems.
If you want to stay in a nice area in Paris that is not too crowded by tourists but still central enough to conduct your city trip - I'd recommend you Sophies appartment right away.

It is not exactly "a few steps" from Champs Elysees but I don't know how literal you take these descriptions. Google Maps is your friend ;-) The area itself had lots to offer anyway.