Also titled in TN, but I would check with your local vehicle registration office - or whoever does that in your area - and also the registrar from the state it would be coming from. If the current owner will give you the info, you might be able to get everything you need to know from their lender.
When we sold our ROO, it was titled in the state of TN, but registered in the county. The new owners are in KY. Their lender worked closely with our lender to make sure all the ducks were in a row and everyone knew what they needed to know. It did take some time - seems like about 30 days - but everyone got what they needed. Buying from a dealer, they should have everything you need to cross the border and handle your registration. Most likely you will owe sales tax in the state you're registering it in.