That requires you to save 50% of your income. For most of us, that requires relocating to a cheaper home, or telling your significant other that she'll need to

That requires you to save 50% of your income. For most of us, that requires relocating to a cheaper home, or telling your significant other that she'll need to chip in just as much as you do. Both are pretty big hurdles. However if you can pull it off, it's great.