Can I register a car from another state in New Hampshire?

Am I able to finance a car (2008 Honda Accord LXP) in my state (Rhode Island), get the temporary plates, and then drive up to New Hampshire to get my car registered and the plates?
P.S I don't have any car registered at all right now, no plates need to be transferred or renewed.

It sounds reasonable enough, you take the title to them get the plates and claim the car for the State of Rhode Island. But it might not work. In California when you register and out of state car the DMV worker steps outside to verify the VIN. One of the more informal moments. But if they do need to check it before registering, there could be a work around.
You could also look into temporary NH or RI plates for the purpose of transporting the vehicle. I'm not sure which state you would go to. You can get a plate for just one day. The DMV is prepared for most situations. You might have to rise in the DMV bureacracy. But as the bible says: happy is he who has been corrected by God.

No you may not, if you don't live in New Hampshire. You must live in the state (where you live, pay taxes, etc) in order to register a car in that state. Usually, your driver's license is also from the same state as your vehicle. If you move to the other state, within a month or two usually, you are required to change both your driver's license and registration.

People buy cars from dealers in neighboring states all the time. You could buy one in New Hampshire and drive home to RI, and register it where you live, without any problems. It must be registered using your street address, where you live. Your address on your Driver's License is usually indicative of where you reside.

It is possible.

To get the car registered and plates from NH you have to have a legal residence in NH and show proof as in a lease or electric bill in your name. Of you have a relative living in NH you could possibly get away with it but still show some form of proof you're living at that address. If your planning on saving money because car insurance is cheaper it won't last long someone from RI will turn you in as in a neighbor. Years ago a heck of a lot MA residents were driving cars registered in NH that lived in MA. State of MA started to crack down and have these residents prove they were legal residents of NH and not MA more than 3/4 of them couldn't and had to register the cars in MA since it was considered fraud trying to get out of paying the excise taxes and higher insurance premium on the car

Well If you buy your car in Rhode Island registered to you home address then decide to move to New Hampshire you technically could. When you move into your home have you mail forwarded at the post office so that way the finance company or dealer can mail you your memorandum. Take that and whatever evidence or proof of residency New Hampshire DMV requires to get solid plates and license.

Just as soon as you establish residency in New Hampshire you can.