If it's your carry gun I assume you've shot it, cleaned it and possibly changed out the site correct? If so it's probably worth about the same as any other lightly used G17. Keep carrying it and shooting it because they aren't worth much more (if anything) at this point.
I have one too and while it's still in the box, new and unfired, I'm not really collecting and will eventually shoot it like any other Glock I own.
- G17(2), G19(3), Gen4 G22, G23, G26