Your parents'. lol

Really though, you just have to shop around. Either a broker or just search yourself. Insurance companies change their rates based on data they collect frequently. I had progressive for a decade, it was by far the cheapest when i got it. Other companies quoted me double.

Then a year ago progressive raised my rate significantly. I called allstate (one of the most expensive when i was first shopping) and they came up under what i was paying with progressive by far.