Budget insurance Value added products are a ****

I hate the value added products from Budget insurance. They have been rude and unhelpful to me. They don't want to cover me for a shortfall. What shortfall is it, they start by separating vehicle extras from the vehicle and say the shortfall is caused by the extras my question is how do they know because the extras amount is added to the initial vehicle amount. Do not take the shortfall insurance from budget insurers