Do them in! Really, do them in! Trust me on that one.
I had them enter via the shore power cable on a project I was working on. They wouldn't go away no matter what I did.
3 years later they had become a total and true menace.
I discovered they built a nest inside my roof of my TT and were breeding there.
Trust me, you DO NOT WANT that. I went through absolute misery trying to eradicate them. they multiplied and they were everywhere.
I finally found a bait they liked, a poison they hauled back to momma and it finally, after 3 years, wiped out the nest, killed them all.
They were in my light fixtures, they were all over my ceiling, in my cupboards, all over the floor, everywhere.
Trust me, take the steps needed NOW and get rid of them so you don't have to go through what I did.