You can reserve rooms. Each room holds 10 people, but you can pay for the full room and make sure that only your group is in there, or just pay for a few and hope that drop-ins don't come in. It's a bit pricey, but I've done three rooms, one with drop-in and two without, and I will reserve full rooms from now on.
Each room can hold up to 10 people
You can book all the rooms. Three rooms in Livermore and Four, soon to be Five in Stockton.
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