Deciding where you want to put the equipment is really important. It has to be in a place where you will be motivated to work out. How motivated do you think you will be if you put it in a dark, dingy basement with no windows or nothing to look at? I'm guessing it won't be long before it gathers its share of cobwebs.
When deciding where the equipment should go, the most important factor to consider is safety. Here are some things to think about when choosing a location for your home gym.
To give you an idea on how much space to allow for various types of equipment, here are some general guidelines.
Treadmills -- 25-30 square feet
Bikes -- 10-15 square feet
Climber/stepper -- 15 square feet
Multi-station gym -- 50+ square feet
Free weights -- 30-50+ square feet