There is also the FAA required Bill of Sale form (if memory serves, it's form 8050-2?).
8050-2 has all the pertinent data that's required to be filled in:
Date of sale, seller, buyer, aircraft ID by N number, make, model and aircraft serial number, etc.
Without 8050-2 there is no legal sale or change in ownership.
This is the form that still uses carbon paper which results in (I think) 3 copies:
The top original page, signed in ink, is sent to the FAA, this is what they use to record the sale and change of ownership.
A pink copy that is kept in the aircraft by the new owner and used as a temporary registration.
And the last one is for the new owner to keep with his paperwork.....it's kind of an extra copy that is not typically used for anything.
This 8050-2 is important (that means vital) and it will trump any other bill of sale related to a sale.
This 8050-2 requires the signatures of both buyer and seller so again, this form is important and it needs to be done.
Post sale, you take your old registration (the form Hung eluded to) out of the plane, fill it out, check the export box and send it in. With this the FAA removes your old plane from the current U.S. fleet of registered planes and the population of the fleet shrinks again.
On a side note which does not impact you but could impact the buyer since you indicate it may be for export:
When Cindy and I bought Mighty Mouse in Alaska, we had to fly through Canada making numerous landings within their borders. Canada does not recognize the pink, temporary 8050-2 copy as proof of ownership......they required the official FAA registration that we all carry inside our planes at all times.
That's Canada and that was two years ago. What they do elsewhere is an unknown to me.
Jim