Thanks for the expertise cindyfan!
It says it's the "total estimate" after base rate, discount, subcharges & taxes.
I used Product Rate Code: WWEB (from national's website) and Contract code:6600330 (from rentalcodes.com). I tried using the Emerald Club code but it didn't give me a good rate. I tried other companies who quoted above $400! So I figured I'll stick to National since Mousesavers says it's a good rental company.
So for a standard SUV, 9 days, pickup and drop off at MCO, unlimited mileage and no extra warranties/insurance, since I have that, is $327.27 a good price? I'm going in September so I wasn't sure if there is "low season" discount. I got it now since I hear that rental car rates are going up.