Based on prior knowledge, the number of doors can be an important factor in determining the rating of a car purchase decision. Here is the analysis of the relationship between the feature "doors" and the target variable "rate of buying a car":

- Unacceptable: Cars with fewer than 4 doors might be considered unacceptable by some buyers who prioritize practicality and versatility. Therefore, the possible values of the feature "doors" for the target class "unacceptable" could be ['2', '3'].

- Acceptable: Cars with 4 doors are generally considered acceptable by most buyers, as they provide a good balance between practicality and size. The possible value of the feature "doors" for the target class "acceptable" could be ['4'].

- Good: Cars with 4 or 5 doors, and potentially more, are likely to be considered good by buyers who prioritize space and functionality. The possible values of the feature "doors" for the target class "good" could be ['4', '5more'].

- Very Good: While having more than 4 doors may not be a deciding factor for everyone, it can be seen as a luxury or convenience feature by some buyers. The possible value of the feature "doors" for the target class "very good" could be ['5more'].

Based on this analysis, here is the required dictionary:

```json
{
	"unacceptable": ["2", "3"],
	"acceptable": ["4"],
	"very good": ["5more"],
	"good": ["4", "5more"]
}
```