Some things to keep in mind, I had not thought of, before contacting a car hauler. I'm sure there are more.
Open or closed trailer?
Pick up window, one wanted 3 weeks, anything time during that 3 weeks and would call 12 hours before. Needed to Coordinate car hauler with moving company, more money, many would not even talk about it.
Drop off window, many said, we'll call when we get in your area.
Do they protect your car if double deck trailer, oil drips, etc.?
Some required I be there in person, for them to load, had to sign papers. One would let someone else sign with power of attorney, more money.
Is the car running, if not more money.
It appeared that a convertible cost more to ship than a sedan, etc.
One hauler even said shipping a low to the ground car cost more, harder to attach straps.
One would not allow a car cover to be installed.
Some would allow owner insurance, with a letter from insurance, one required you to purchase their insurance.
One company would not deliver to my house, recommended pick up in Las Vegas, NV.
I have only looked into shipping once, I got the idea that they (shippers) like shipping from one dealer to another, or to a scheduled auction.
Has anyone that ships cars more often, written a tutorial on what to look for in a shipper?
This was about three years ago, I'm sure I do not remember everything. I always thought of myself as a detail oriented person, but car shipping has so many things to think about, it gave me a head ache.