One of the sore spots in the Real Estate Industry is a missing reputational model for evaluating professionals and their services. Since there isn't an open and neutral model which already exists, I started modelling a potential application. Below is a use-case diagram modelling potential actors, scenarios, and associations for an application:
As you can see, I've defined just three types of Actors: Professionals, References, and Guests. I've also defined two external entities, OpenID and a web service. The scenarios listed are a first pass and expect to refactor their associations while adding/removing some. I won't go into detail here regarding the scenarios, but if you would like to follow the wave and/or offer comments, please feel free to contact me on google wave. My gwave account is email@example.com.
My next step in this process is to create component, deployment, and behavioural diagrams. I'll post these also to my blog in the future.