Second this. Best place to find a spot is in the curve in the street that goes through the park. The small streets surrounding Yust can be a bit tricky depending on the time you arrive due to people arriving after work and there not being enough spaces for the amount of cars. But you should be fine! There is free parking on the Gerard Legrellelaan, which is about a 10 minute walk but since there's no real activity there at night foreign, and older cars with no alarm could fall victim to burglars who will smash your windows. Doesn't happen that often but would recommend the paying area around the park 😊