Rat in Van

Saw some evidence of rodent in my van today. Still no idea how these bastards keep getting. Set a snap trap at around 5, came out at 7:30 and the trap was gone…oh no. My car is pretty messy, mostly clothes and stuff my mkds .but I looked with a flashlight and didn’t see anything, I also rattled a broom around under the seats and didn’t hear anything. Going to wait until the AM for more light.

My question is how the hell so do they keep getting in. That’s 3 in the last year. Mechanic looked and didn’t see any openings that he could see. I don’t want to have to keep dealing with this it’s gross and they are destroying the interior of my van.