How do you recycle?

From my personal experience, don't do it. I've only sold a couple of guns to fund another gun project and later regretted that I did. We don't buy guns as an investment, at least I don't, so maybe you just need to look into additional storage solutions.

Meh, if they are easily replaceable you can always buy another down the road. If they are hard to get or more sought after you will fetch more of a premium now selling them but if you have sellers regret and want to buy another you will pay even more later. The used gun market/value is slowly coming down but still on the higher end, depending on what you have. Keep in mind there is always the chance that if laws change for the worse you may not be able to buy it/them again in the future.
With that threat as precedent as it is, I’d only sell to replace, not “for profit”. Plenty of options out there to sell used firearms. Some are free and some cost $

I've never once had sellers remorse. If a gun no longer has a purpose in your life, I say sell and upgrade, find what will be.
I am not getting into what I have sold, but I have regretted giving 4 guns away, 3 of them were 22LR.
You could die tomorrow and now your wife needs to deal with the bullshit, when the money could have been in your bank account.

I’ve regretted getting rid of a handful of guns in my life. Some were more like lust, and I thought I regretted it but time proved otherwise. Some that I have parted ways with have haunted me since the day I sold them.