I don’t believe in selling guns. Even if I never look at it again 
I have sold a few though. Early on I decided that I wanted all my guns to be functional in an every day way. That does not mean that they all have to be simpleton guns, but they needed to be functional for HD, hunting, or whatever. Not necessarily ideal. So, a bolt action mil-surp passes because it is functional. Not ideal for anything in modern times, but can be used to hunt, SHTF, etc.
In early 94 I sold a MAK-90 type gun [actual number was something else like NMH-91 or something but it was typical early 90s thumbhole AK] in 223. I’d only had it about 5 months but had bought my first AR receiver and decided I did not need it and wanted the funds to build the AR. This was before my “functional gun” decision.
I later bought an Eagle Arms AR that had a 24" super heavy barrel and free float tube. I put a scope on it and enjoyed shooting it. It was like shooting a heavy barrel 10/22 and scope – you can watch your hits through the scope – but you were shooting 223 instead. It did not move when fired. However, after having this a while, I came to my “functional gun” decision and decided this was too heavy to be one, and I sold it. Except for some cast AR receivers I bought in 2004 when I was cash poor but wanted to get something in hand under the belief that the AWB would be reinstated, and that I later sold after BHO’s election in 2008, I don’t think I have sold any more guns.
That does not mean that all my guns get regular use. Most don’t. But I still like having them. Some still have their cosmoline or cosmoline equivalent on them after 12 years of sitting in their boxes (think Ishapore Enfield 2A) but some day I will get around to cleaning them up, having them inspected, and shooting them or making something out of them. Same for the old pitted VZ24s I bought for their actions back in the 90s…
If I had the resources, I would agree with SteyrAUG and his “reference collection” ideas for myself. But I don’t. But it appeals to me.
Now, the ones I do deal with on a more regular basis are my functional ARs and my M&P handguns. My first go-to guns if I were to need to defend myself and my family. I don’t do much plinking any more (though I hope to change that as I get my son involved in shooting, and eventually the daughter [he is 9, she is 4]). Any time I spend shooting is to (at least on paper) develop or reinforce certain skills and training.
But the other guns are nice to have, where ever they may be 
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