Idaho includes a tear-off bill of sale with the title. You just take that in to the court house and request a new title. You might even be able to do that through the mail.
I’ve bought two used and one new car in NH and sold two used cars there; none of the bills of sale were notarized. I also brought 3 other used cars from out of state into NH, no notary there either.
https://www.autotrader.com/sell-car/in-ID
According to https://notary.pandadoc.com/knowledge-center/does-a-bill-of-... only Louisiana, Maryland, Nebraska, New Hampshire, Montana, and West Virginia require a notary on a bill of sale.