All of the companies, and possibly even different agents, will have different policies and responses. But always keep records of what you had, pictures and/or receipts. It never will hurt and only help. I was told I needed to increase my insured amount when I mentioned the aftermarket parts increased the value of the car a lot (not a small fraction of the cars worth).
But there is no blanket answer because costs and values are different. Let’s say you have a car worth $40K and have it insured for $40K. If you have a stereo worth a grand and it gets stolen. That $1K in losses is 2