Aside from the obvious security reasons: When selling it's all about perceptions and presentation. The house should have minimum furniture and "brick-a- brack" including reloading stuff and firearms related stuff! It makes the space look larger and open. (Including the garage!) Follow the selling agents advice on this issue!
Move the stuff to the new house or storage! You'll thank me later!
Moving guns to a son or daughter shouldn't be a (FFL) problem unless to another state! Of course verify that they can possess firearms! Yeah I know, but it could happen!
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