[Noah930]

Short answer: every state is different. I don't know what it's like in Florida.

You have two concerns: cops and insurance.

If you get pulled over during transit, the car is obviously not yet titled/registered in your name. In my case, the PO of my Porsche was kind enough to keep the car titled under his name until I mailed the plates back. But that's a big extension of trust which is probably quite atypical. You'll have to call or visit your DMV to get the proper paperwork, if you want to do it the right way. Some states will allow you to have a temporary "plate" for a few days. I knew guys who used that as a 3-day pass to drive their non-street-legal race cars to and from the track for race weekends up in Washington. Easy answer is to just not get pulled over. But if you go bandito, it's worthwhile to have as much documentation (bill of sale, pink slip, etc.) in your possession.

For insurance, like you point out, usually a call to your agent the day before picking it up will have the car covered for x number of days until you bring it back home for proper registration/etc.