Book this place. Don't question it at all, there's nothing like it in the world, and definitely not in Austin. It's truly magical under that oak tree. I booked it for my (work) team's offsite--11 of us stayed here, and the rest of the team (22 in total) spent our days here working and workshopping in the different, wonderful spaces all over the camp. Whatever your need, it will more than suffice. And if your heart desires the smallest thing (pollen in my airstream, BBQ delivery, groceries for the group...) Miles will go miles and miles to fulfill it. He and his team really showed my team what gracious southern hospitality looks and feels like, and we're forever grateful for it.
[If you're curious as I was, it's 4 bedrooms, 6 airstreams, plus 1 tent and 1 semi private bed, which will get you 10 fully private + 2 semi-private individual spaces. If you add all the extra beds in the airstreams and tent and elsewhere, I'm sure you could fit upto 25, maybe 30. There was more than enough space in the TV room and lower deck to host our group of 22 for meetings. If I was coming to Austin in a larger party for a good time, I'd come back here again in a heartbeat.]