We've got a lot of five star ratings for cleanliness, accuracy, value, communication and arrival but sometimes, even though we get five star ratings on these, we don't then get a five star rating overall. Perhaps you could adapt the system and allow people to rate for those five things and then present them with a statement, "so overall you'd rate the property as (the average of the five)", giving them then the option to click "yes" or "no" and then say why not. That would perhaps give greater clarity and require people to justify their actions.
