Space, budget and purpose
The number one concern when creating a home gym is what are the main purpose behind the gym (is it to get fit, to compete in a certain sport, to become a better dancer, to perform yoga at your residence, to train for a marathon or esc,.), how much space you have and how much of a budget you have for the assignment. Once you have figured out what activities you would like to do on a daily or weekly basis then you will then have to figure out your budget. If you have a shoe string budget you may have to build things own your own, find gym equipment that others no longer wish to have or if you have a big budget which means you can splurge a bit on what you really want and make it world class for anyone. The simple fact is that it has to make sense for your budget and the purpose behind you deciding to build a gym at home.