The gun and a receipt from the dealer.
You may sell it to a dealer, have a dealer sell it for you, or you may sell it directly to another resident of Arkansas so long as they are old enough to buy a handgun, and you do not have reason to believe the buyer is not able to legally own a gun. If the gun is being sold to someone in another state, the gun must be sent TO a gun dealer in that state.
That depends on your states laws. Some states allow it; some states require all handgun purchases to be made through an FFL dealer.
Rifle or shotgun, yes, if they appear in person at the shop. Handgun- no.
It depends on where you are. In some U.S. states, you can sell a handgun between private parties with no paperwork. In some states, you have to go through a gun dealer.
Purchases from a dealer are governed by Federal law, not state. 18 for rifle or shotgun, 21 for handgun.
(in the US) No, it is perfectly legal. However, depending on where you are, there may be stipulations. In most U.S. states, you can sell privately owned firearms to anyone that can legally own the firearm in question with no paperwork required, however, a few states require the sale to be processed as a transfer through a licensed gun dealer, which will involve some paperwork and a fee. Some people sell privately owned firearms through dealers even though it isn't required in that person's state so there will be a record of the sale. Also, regarding handguns specifically, in the U.S. you can only purchase a handgun within your state of residence, so if you are selling a handgun to someone in another state or if you are purchasing a handgun in a different state that where you reside, that must go through a licensed dealer in the state where the purchaser resides. Additionally, all of this applies to non NFA firearms. NFA firearms are machine guns, supressors (silencers), short barrel rifles and shotguns, and a few other things.
No real age limit to sell to a dealer. Possession is a different matter.
See a New York Firearms Dealer with a license to sell pistols. Federal law requires that you may only purchase a handgun from a dealer in your home state. They will have information on the FEDERAL as well as STATE requirements.
Not from a licensed dealer in the US. Some states permit a private purchase, but Federal law will not permit a dealer to sell any gun other than a rifle or shotgun to anyone under 21.
I'm pretty sure Texas doesn't have registration, and there is no national registration, so the answer is, basically, you can't, because it isn't "registered" to your name. If you are selling a handgun and want proof you don't own it any more, sell it through a licensed dealer, or if you sell it by private sale, get the buyer to sign a bill of sale.
Yes, you do not need a memorandum to sell a car. You need a title and a bill of sale.
YES THEY do