A fair deal

”I can take care of your rat problem.” You say.

”There's a highway man and other stuff as well.” He ponders.

”But you ain't going to retrieve them yourself?” You smile.

”I hate rats!” He frowns.

”I'll give you 50 gold coins for the key and the book.” You suggest.

”Deal!” He says.

He walks to the bookcase and takes two books. First one is Vault Tec Journal and the second one has the key inside. He gives them to you.