if your credit is already in the 700 range, you'd be better off showing some consistency. when you're buying a house, they always say do not do ANYTHING that might raise a red flag to a financier.
that includes trying to apply for auto finance, credit cards, etc. I'm no expert but I'd also assume that means you don't want to start messing around trying to "game" the system for an extra 10 made-up credit points.