The conditional issue takes precedence over conviction: just because a local event exists doesn't mean it should dictate the trip, especially if the constraint is the main concern.
First, establish a threshold of financial tolerance before getting excited about the destination.
If, for example, a big concert in Brussels causes hotel prices to skyrocket beyond the family budget, the destination is no longer viable, regardless of the event's appeal.
The warning is clear: local events can rather be a disqualification factor for most people.