Let's look at what would happen if the same man were to wait until he was age 30 to start saving. It's the power of compounding. The sooner you start saving, the longer the money has to grow. Putting money into some type of a retirement account is a good idea, both for the savings and the tax benefits. One thing you do not want to do is put money you are saving for a home or some other short-term goal into this type of an account.
Some people have borrowing privileges against their employer's retirement-savings plans.
With these arrangements you can fund for your retirement, reap the tax benefits, and also borrow your own money for the down payment of a house. Be sure that you understand that this money must be paid back, and what those payments will be. It is important to keep in mind though that these lower down payment mortgages have additional costs added into them. It protects the lender financially in case you default. PMI is not a permanent cost.