Calm British Shorthair cat raised in an apartment

Our British Shorthair cat has lived with us for about three years. He's a very calm cat who spends most of his time by the window or on the sofa. He's not the type to run around the house, but he likes to stay close to people when someone is in the room. He's perfectly litter-trained and has never caused any problems in the apartment. The only issue is that we have to travel often for work, and the apartment is empty for long periods. We think he would be happier in a home where someone is there more regularly.