When you are doing squats, make sure to put your body weight on to your heels. By doing this, you are making sure your knees do not have too much pressure on them. Do not squat too low; find a squatting position that has your thighs parallel to the floor.
If you have severe asthma or cigarette smoke allergies, make sure that you speak to your future landlord about whether there are non-smoking units available or how many people on average, smoke nearby. Many apartments suffer from this problem because they do not separate the apartments by smoking and non-smoking.