Yes.
There are states that don't allow certain types of guns Most states have restrictions on guns for felons In the US no state has a complete ban on firearms as protected as a right by the 2nd Amendment Certain bans on handguns have been attempted with weak results that have been reversed in the Supreme Court
Its called ebay. I'm pretty sure eBay won't allow guns. You can sell guns on gunbroker.com
Yes. About one third of us that are adults do own guns. Legally.
See link provided below.
no definately not!
No. There are no urban areas that allow paintball.
18 for long guns 21 for hand guns
Despite belief to the contrary, in MOST of the US, there is no requirement to register ordinary guns.
Trade
Yes
No: neve,r You have to put in in a suitcase and declare it before it goes in the luggage compartment. NEVER try to take it into the passenger compartment of the aircraft.
No one record. Estimates are about 310 million guns.