Weddingbee boards

Hello, I need some help on my centerpieces.  Just visited a florist yesterday and trying to cut some cost down on the centerpiece. 

Here is what she quoted me:

$40 a piece for

short square vase (rental as part of the centerpiece)

green hydrangeas + white roses + dark purple carnations

Is this price competitive?

She keeps insisting I should keep the flowers theme the same for the wedding so she re-use same flowers for the bridesmaid bouquet.

Would it be okay to pick some other flowers but within same color theme as my wedding?  Or is it odd to pick different flowers than the rest of the flower decor?

My venue already provides a 12 x 12in mirror and a few candles.  Right now I will need 12 centerpieces + long 12 ppl headtable centerpiece. 

Any idea how I can simplify the centerpiece so I don't need to spend a lot on the flowers?  I thought about getting my own vases but not sure what kind of flower to put inside to save cost and still look okay.

Any feedback will be appreciated.  Thanks!

I say DYI the centerpieces. And yes, you can use the same colors but different flowers. Try places like the dollar store, they usually have a wide selection of very basic shaped glass vases for what...$1 and then go wholesale for the flowers ( I recently found out that Sam's Club has wedding flowers both bouquet packages and loose flowers for VERY reasonable prices) . We are doing whole sale flowers in shades of white, cream, pale green and pink in mason jars (we can every summer so we literally have 100s laying around) wrapped in lace and ribbon. My bouquet, MOH bouquet, and boutineers, will probably be te only thing we actually order from the florist.

we are ordering the flowers from a florist but i am arranging them myself. what they really charge for is the arrangments! also. smaller vases means fewer flowers which means less money. or skip the flowers and do something else...we're doing vases with betta swiming around inside!