Your centerpieces must be not necessarily sumptuous and whether you want to cut the costs here our advice: instead of placing a round flower centerpiece just add a simple candelabra you can hire for Euro 15/20 maximum!
Ask to your wedding planner or florist to arrange something nice:
Option 1: place your candelabra on a round mirror and put some confetti or petals.
Option 2: ask your wedding planner/florist to put some single flowers at the bottom of your candelabras.
Option 3: ask your wedding planner/florist to prepare some simple bunches to be tied in between the arms of your candelabras.
Option 4: (if you had extra budget) ask your wedding planner/florist to prepare a round baby breaths garland, this will be stunning on the bottom. Then as to prepare a big round bunch to be put in the middle of your candelabras. Hang some crystals around the arms and let them floating in the air, some crystal pendants are fine too.
P.S. Do not hire too tall candelabras, an average of 25cms height is fine. Taller will not allow your guests to talk each other.