I did some more digging and the cheapest lodging I've been able to find within a reasonable distance to the con is the Ibis that Codaulux mentioned in the old BUCK thread. The Ibis has a free cancellation policy up until the day before check-in so I went ahead and reserved three double rooms and if something better pops up down the road we can always change our plans.

Unfortunately, there's a two adult per room limit so we'll need an extra room (the thought of sneaking the 3rd person in crossed my mind but I'd hate for somebody to travel that far and end up being left out in the cold). The total for the weekend still isn't too bad at least, if we can manage to get six people it'll end up being €70 per person for the entire weekend (July 28-31).

Any thoughts or suggestions?