NY doesn't require you to sign in front of a notary. While a bill of sale is generally valid without notarization, there are situations where it becomes a wise precaution.No. A bill of sale refers to a legally binding document that confirms that you actually bought that vehicle from a private entity or party. For most private vehicle sales between individuals, a bill of sale does not need to be notarized to be considered legally valid and binding. To file for an assessment appeal, you must timely complete an Assessment Appeal Application (form BOE-305-AH). Document you want notarized. You can fill out the information on your document, but make sure you do not sign the notary until you arrive.