When considering condos there are several important items to research and consider. One is noise. If you're not on the top floor, can you hear your upstairs neighbor, and if so, how much? Some buildings are built so poorly that normal walking upstairs actually shakes the lower apartment. Other buildings you can't hear anything when the person upstairs is jumping up and down. You might think you're in the clear if you purchase a top floor unit, but if you buy into a building that actually shakes, your downstairs neighbor will be knocking on your door within the first 2 weeks of your purchase suggesting that you buy slippers, extra rugs, and in some cases will be downright beligerent or ignorant of the fact that it's not your fault simple walking is so noisy.
So what do you do when buying a condo? Check the CC&R's for rules about floor coverage. Some require 100% carpeting, usually with the exception of closets and the bathroom(s). Others have high percentage floor coverage like 70% so you must have a large area rug in the all living spaces. Still others have no rules at all. In 100% or high coverage condos you can buy a bottom floor condo and get hardwood floors if that's your preference and feel fairly confident that noise levels will be low. But I strongly suggest you do a test for noise. Ask to get access to the upstairs apartment to do a test. If they say you can't, press for it. Chances are the person above you would rather have any issues arise before you move in vs. you knocking on their door and complaining all of the time. And the Listing Agent and Seller would rather avoid a troubling law suit after you're in. So they may all comply - a quick tip - request this after you are in contract, but make sure you've got an Inspection Contingency from which you can make this request.
You can also do your own tests without getting into the upstairs condo. Walk around the condo with heavy steps. See if you can tell if it's causing shaking or seems like it's making loud noises. And one final tip, buildings built in the 60's, 70's and early 80's seem to be most prone to louder noises and shaking. Ask your real estate agent what he or she thinks about each building you visit if noise is an issue for you. And if noise isn't an issue, you'll get to buy more affordable places.
Ahh - one last tip. Bottom floor units that are actually the second floor because the ground floor is the lobby and garage.... if your condo is above the garage, make sure you do a test of the garage door opening and closing to see if the noise and/or shaking effects your condo. Usually this can be fixed or at least reduced, but it can still be an issue.