can anyone tell me how much i could get for a used 20 gauge Remington 870 Express Magnum Youth shotgun? it's about 12 years old, wood stock, almost looks new, i don't even think 100 rounds were fired (maybe 50-100). everything works, cleaned after every use. i have no idea how much it'll be worth and don't want to be ripped off. if you can help that'll be great.