Is there overnight camping?

No. And there is no homeless hanging out.

I wouldn't to many homeless and they love to speed in the parking lot.

Ya, I see people doing it all the time.

I always see them there

I see campers there a lot actually. As long as it's super short term (1, maybe 2 days and nights) then you should be fine. There's even long side streets to the west with desert lots that you could get away with a few nights I'm sure.

Nop. It will close at 9pm.

Yes a lot