For my first gun I was debating between a Ruger SR9 and a Sig 226 (both 9mm versions). After agonizing over the decision, I bought the SR9 because of the price difference and the fact that I was inexperienced and this was my first gun. 30 days later I went back to the same gun store and traded the SR9 for the Sig 226 which I still have. They gave me $300 for the SR9 toward the 226 which had the asking price of $around 800 so I don't think I came out too bad.
As an addendum to Cheapshooters rule, I would like to suggest always get what you really want in the first place as you will probably end up with it anyway at a significantly higher cost
Do not follow where the path may lead, go instead where there is no path and leave a trail - Ralph Waldo Emerson