Check out Sam's Club's website and your local wholesale to the public florist for bulk/wedding flower prices. At the end of the day, it all depends on what blooms you want and how much you want to spend. You can go to your local grocery store, purchase a few bags of their cheap mixed bouquets, tie them up and have them done for $100 too. It's all in what you decide to do or want to spend.. The more flex you have the more friendly your budget can be. That said, consider the time and the mess. This is a last-minute project which makes a gigantic mess, the value of your time is incredibly high the day before/day of your wedding, is it really worth the stress for the few $$ you'll save. You could purchase one of their wedding packages and it's all done for around $500. The more flex you have on the design the easier it'll be to keep it on a budget you're willing to spend.
One thing to try is give your florist the amount of money you're willing to spend with the list of needs and see what you can get for that amount of money. I was surprised when I was searching through FTD (MIL's B-day coming up), and there were bouquets more elaborate than we had for our wedding for less than half of what we paid many moons ago.