I am sure your father has a big client _base_ to reckon with. Yes, you will be happy to know that he can actually retire and earn a pension!! There are referral services to help out people like him. They will kind of buy out or make use of the client data_base_ and have him as a key referral agent. He will have the liberty to choose his team of active field agents, who will be attached to him. Such services are easily available on the internet. One such site that I recommend is
www.MyGreenParachute.com. They will take care of everything and your father will earn referral fees as a referral agent. He can also sign up on their blog site
www.JoinMGP.com for exchange of ideas in the real estate business.