If you do end up moving, I'd ask questions like, "What is between the apartment you may end up renting and the one above?" And, "What is the construction BETWEEN the walls?" (If you can 'prove' it too, that would be good for peace of mind.)
Here's a true situation I was in. I use to live in Weymouth, MA right next to Weymouth Naval Air Station. I was about 200 yards from the end of runway 24 North. 98.5% of the time, this runway was used for landing. I was as close as anyone could get to the end of the runway. I happen to love jets flying low and fast. I qualified, 2x's, to Go Navy but a relationship the 1st time and change-of-heart the 2nd time kept me out. Nonetheless, I consciously chose to live where I did. (It was REAL entertaining during Desert Storm!)
Anyway, I was on the bottom floor of a 3-story apartment building. (The one 'behind' me was 4 stories, and the one behind that was 5 stories. The buildings were kinda tiered-down as the complex got closer to the runway.) Moving right along ... My unit had brick for walls and baffled ceilings. The brick walls speak for themselves. The baffled ceilings are designed to carry any sound to the 'ends'. One end was to an outside wall, the other was to the hallway. It was incredibly quiet. The only point I'm making is that, fortunately, the building was designed well for noise supression. The aforementioned 2 questions are the type you want to ask. I empathize because I've been there, done that. Now, I'm married w/children and have a single home. Fortunately my neighbors are quiet by any standard. I can't wait for the kids to discover the drums and the boom-box.