Chick:
I am a banker, albeit, a commercial one, not consumer. What you've described sounds like good potential for a great credit rating...but there are other factors (it's a top secret black box that is more protected than the secret formula for Coca Cola).
Be Self Aware: If you're interested in getting your credit bureau, you can go to www.freecreditreport.com but beware, I don't think that it's "Free" to get your actual credit score.
Don't Just Compare on Rate: The two week lag in getting the 'best rate' from the credit union can wind up costing you more...say you save 1/2% on the rate (about $150 over four years on a $15,000 loan)...you could save considerably more than that by being able to negotiate a better price by having the loan "locked up" or getting it through the dealer. In other words, the dealer will not negotiate the best price if they have to wait two weeks to close the deal. Use www.edmunds.com to help determine fair value of the car you're considering.
My bank doesn't do many car loans primarily because we can't compete with the rates that are offered through the dealer. SO, I recommend you pay a few $ to get your actual credit score...if it's over 750, then you'll be able to get the best deal possible with a low/no down payment. If it's over 700 or 720, you'll still get a good deal, no matter where the money comes from.
Strategy: Also, you might consider working with a male salesman. WHile they've gotten more 'sensitive', Silver and I learned long ago that many don't know how to negotiate with a strong-willed woman...and this tends to accrue in your favor.
Beware: If you know your credit score and the dealer asks for your name/address/ssn BEFORE you've picked out a car, give them your credit score instead...otherwise, they may be running a credit bureau report on you and every time someone (not you) pulls one, it's about 18 points off the score. SO, save them the trouble in 'prequalifying' you by giving them the score and making them wait to pull the credit bureau once you've settled on the car and the price.
Sorry to be so long. Good Luck

