We were at Vero for 5 nights last August and rented the umbrellas 3-4 days. We would leave our beach stuff on the chairs and go up to the pool for a little while and then come back. We found the sun so hot in August, that we needed the umbrella on the beach. And since we flew in and out of Orlando, we couldn't bring our beach equipment with us.
If you have a roof top carrier - I'd bring them...it will be much less expensive since you're staying two weeks. If you don't have a roof top carrier.... you might want to consider buying one! We got one from Sears for our mini-van and use it for beach vacations. We put all the beach chairs, toys, umbrellas and towels on top of the car and use the carrier to ferry the stuff to and from the beach. This way....much of the sand is on top of the car...rather than in it!!!! At Vero you probably won't want to store the stuff in your room, and you won't drive the car to the beach (unless you decide to go up to Daytona), but you might use the car as a storage unit. Unfortunately, the rooftop carrier might make the underground parking an impossibility for you.
There are a few pros and cons for you!