Parks in the San Fernando Valley that allow jumpers for kids birthday parties without renting a permit?

At El cariso and at veterans you have to rent a space and the people who rent out jumpers need to have a permit. I know there’s parks that don’t need anything but to get there early and I’m wondering if you guys can recommend me some. Nothing too far. Surrounding areas of Mission Hills, Granada Hills, Sylmar, San Fernando, and Pacoima.