$900 is not that much, I'm actually surprised it's so low.
A GDC All Access pass is $1,950, and a GDC Main Conference pass (typical) is $1,350.
A GDC All Access pass is $1,950, and a GDC Main Conference pass (typical) is $1,350.
And Joel Spolsky's "Business of Software" conference is $1600 for two days, and Microsoft's PDCs were $2200 for 3 days.
This is about 1/2 of the market rate for major multi-day tech conferences.