Who Can Elimate Rats in a Detached Garage Attic?

We have rats occasionlly going into the attic above our detached garage. I have a webcam up there so I've captured them multiple times. It's almost always one, but I have seen two at the same time occasionally. We'd really like to hire someone to come out and take care of this. Any suggestions for a company/professional that can help? I don't want to be forced into a retainer. I'm hoping they can just solve this issue and hopefully prevent more from going up there in the future. I know this is a complex problem because I'm sure the garage is like swiss cheese to them with many points of entry, and fully sealing those up likely isn't feasible. But I'm hoping that maybe a combination of traps and some kind of deterrent is a possibility? Open to suggestions!