Since you asked:
Winchester 1300, 5 rounds 00 buck in the tube, empty chamber, safety off, trigger lock.
I could see bird shot if one lives in an apartment, but you are trading stopping power for less penetration (and bird shot will penetrate drywall also). 00 buck is the way to go, generally.
No accessories, because I think slings, sights, extended mags, etc., just slow you down, negating one of the main advantages of the shotgun. One of these days, I'll get a taclight for it...I'd load slugs in the side-saddle, if I had one, but I'd rather have a rifle if it came to that.