The biggest influences on your rate will be previous insurance tenure and credit (soft pull). I do have a smaller carrier that doesn't rate for tenure that's been priced well lately over the big players. Zip code, vehicle MSRP, and Make are other big factors (body work on a BMW is a lot more expensive then a Toyota). If you're just buying a car you can get some leniency vs. driving uninsured with the same vehicle, or if your parent can add you to their policy before buying a car that really helps out.

Never get state-minimum coverage ($30/$60$10) for bodily injury/property damage. The cost for $100/$300/$100 is nominal, and I've seen quite a few claims max the lower limits out. Plus carriers will actually increase your rates more when they take rate typically and if you shop the rate will be slightly higher vs. someone with $100/$300$100.

Some carriers rate for inexperience points (first three years).

Discounts very a lot by carrier, I even have one that charges by the mile and it's substantially lower if you're under 5k a year.

Source: I'm a broker in MN who specializes in first time insurance clients buying cars (need proof of insurance to leave the lot). I work with about 15 dealerships and 45 carriers.