How are some ways you saved?
1) Put everything that I can into my 401K - pre-tax dollars means 30-50% gain right off the bat.
2) Bought real estate financed by the owner and kept my previous residences, renting them out. Let the bank take the risk, leveraging your money. For example, if you put $10,000 down to buy a $100,000 house and that house goes up 5%/year you are making 50% on your money **annually**. HUGE returns. But, it takes work dealing with repairs, the tenants, etc.
3) I built my recent houses rather than buy already built. In the D.C. area you can make upwards of $250,000 on each house by building it yourself. If you don't know how to build do modular - it's already built and is delivered in sections.
Again, it's two jobs - my full time job and the real estate, but I wanted to save for retirement.