Couple interesting points:

1. You can realize over $100k in gains per year without federal taxes if youre married and have no other income.

2. You can withdraw Roth IRA contributions at any time for no taxes/fees. Example: you contribute $5k/year for 10 years starting at age 25. At age 35, it's worth $70k. you can take out $50k and let the remaining $20k continue to grow (house money).