Assuming it's the only Rivian in the seller's account? If so, they should just go in and remove their personal information, credit card, if entered and give you that account, then you can change the info over time to your own, including changing the e-mail and password. But at least that way, you have app access immediately. I've sold several Tesla's and always used a new account to purchase each one, almost solely for this purpose. Tesla was also VERY slow to transfer accounts, plus make you jump through a bunch of hoops. They didn't sell it or make money on it, so I guess it's not a priority item for them. Guessing Rivian will be the same. Would ask the seller to give you the original account as they likely don't need it. Only if they purchased more than one with the same account does it make it not a viable option. Otherwise, as the seller of any of my personal vehicles, I always want the buyer to have the best experience. Tesla always kind of spoiled that new car excitement with their attitude and delays in getting accounts switched over. Generally always too well over 30 days.