The Brew Cabin

I just had a new cement paver driveway put in. I would like to have it sealed. The contractor reccomended a power wash before sealing to remove any cement stains from installation and any others that occured since installation two weeks ago. My concern is that power washing will remove some of the joint sand. Would joint sand have to be replaced and / or vibrated in again after a power wash?

Yes - power washing will blast out the jointing sand, and it will soak the blocks, so they'll need to dry before sealing.

I wouldn't seal a driveway so soon after laying. I'd leave it until the back end of the summer, give the jointing sand time to settle and bed in properly and to ensure I'm not sealing in effloresence, which is a common feature of concrete (not bloody cement!!!) pavers.