As far as the 60% rule goes, you don't necessarily need to get the balance up that high, but don't go over it. It doesn't really make too much of a difference if you charge $10 or 40% of the limit, as long as it reports a balance.
In this situation, I would suggest a Home Equity Line of Credit rather than a secured credit card, simply because interest rates are generally lower, and the interest you do pay is generally tax deductible.
Basically, your friend was right, it is very similar to a credit card, but the collateral for the loan is your home.
If you have any more questions or I missed something, just let me know
