There's no way that garage will be big enough for VB, the hotel, and the convention center, especially when Sapphire is busy and/or there's a convention going on.
EDIT: Looking at the space that garage is going in, even though it looks like it will be 4 floors tall, I'd expect the capacity to be somewhere between Cabana Bay's garage and Portofino's. Likely closer to Cabana's.