Here the author sets up several plot points and creates tension. Ove will be vacating his house, as evidenced by the impending real estate agents, and it's very important that Ove install this hook in his ceiling. We also see that Ove is reeling from being forced to retire. This represents a major upset to Ove's routine and his conception of self. Notice that Ove believes that he has no purpose without a proper job. He defines purpose as having something to do outside of his home that receives monetary compensation.