Using a masking tape you can hang balloons on walls as well as party streamers. Yes I have done this many times and it has not taken any paint off from my wall, nor has made any sign or dirt from the sticky part of the masking tape. The trick of sticking balloons on wall is to cut about 3 to 4 inches strip of masking tape and roll it to each end, make sure that the outer part is the sticky part, then stick it to the balloon and then to the wall. You can use the same procedure as hanging a streamer, but it may require more strips of masking tape as a streamer is usually heavier than a balloon. The balloons should stick on a wall or ceiling using the masking tape procedure for a day or two, so I would recommend that you start sticking on the day of your party.
On the picture the big balloons are not floating, they are stick on the ceiling using a masking tape.