No doubt, you have figured out by now that the key to symbolism is context. One single symbol can have a hundred different meanings in a hundred different dreams. This is why the Holy Spirit is absolutely necessary in biblical dream interpretation, because without Him, it is difficult to choose the correct meaning for the symbol.
It is important to note that there are positive and negative meanings for just about every symbol. Consider the context to determine which direction the symbol is pointing. For example, a red apple in a positive connotation could represent something you love that is healthy for you (red = love; apple = healthy, as in "an apple a day keeps the doctor away"). In a negative connotation, the red apple could represent something that looks sweet on the outside but is toxic if you sink your teeth into it (many cartoon princesses can attest to this).
As an illustration of the importance of context, the "if this, not that'' technique is very helpful. Consider the following dream and the implications of changing a single symbol. For this demonstration, the meaning of the symbol is placed in brackets. You dream that you are driving [you are in control] a red [wisdom] Infiniti car [ministry of eternal purposes] in the state of Arizona [state motto is "God enriches"].
The message could be that you have a ministry to passionately enrich the lives of others and prepare them for their eternal purpose.
BUT – What if a thief and not you were driving? The message would change to indicate that the enemy has somehow' gained control of your ministry and is driving it, and you need to get it back.
BUT – What if the car was a taxi and not an Infiniti? The message would change to indicate that you have a ministry to get people to where they need to be, thereby enriching their lives.
BUT – What if you were parked and not driving? The message would change to indicate that you are stalled in your ministry and getting nowhere.
Context is everything.