Maybe they could film the sequel to "Joe's Apartment" in your car, and make "Joe's Celica." Then you'd have all the money you need get rid of the roaches.
Seriously, you live in Hawaii; Hawaii's got roaches. Any food left in the car, like crumbs, will attract them. I dunno, just keep the food out, and spray it every now and then, especially around the doors. Or try calling an exterminator; maybe you can get it treated with the same long-acting stuff they use for houses.