Does anyone know if the GAS tour guide will make reservations for beer tents during Oktoberfest, or should we book reservations now on our own?
Do not know anything about GAS, but many tour places will guarantee you a seat in a tent for a premium price. To make reservations on your own you need to reserve a ten person table and a spend minimum of a Mas beer and a meal, so 20 to 25 euros per person. The tour places are usually 50 to 100 euro per person, but you only need to reserve by the individual.
However, if your schedule allows weekdays, you can walk into just about any tent in the afternoon and find a spot for 2-4 people. Tents are busiest on the Weekends, Lunch, and after 5:00. If you pay a tour place, make sure it is prime time.
We had a free weekday afternoon on the GAS tour and just went to several tents without any reservations.