how do you know if it is undisputed until it goes thru probate? I recently signed my rights away on a will for a relative. I was not named in the will, but legally had an interest. If I hadn't signed they would have sent registered mail to make sure all possible interested parties were notified. I would assume you need all these people notified before anyone can be determined as "undisputed". This may go beyond "close" family.
I would expect if a car is put in a living trust, then it could be retitled to the beneficiary at death outside of probate.
I don't know the answer to your question. I was told by an estate attorney that all heirs have to sign the affidavit indicating that they are the only known heirs of the deceased. And it has to be notarized. But no other documentation is required.
My former boss at Megacorp did this when his Dad passed a couple years ago. He also inherited the house (via TOD deed) and a few fairly large financial accounts via TOD/POD/beneficiary designation. But the remaining estate was not probated because it only consisted of two vehicles and a house full of furniture and other personal effects. He is an only child and he's the only one who signed the affidavit.