New player question: What to do when your build is “finished” and item slots are full?

Hey all, new Deadlock player here!

I’ve been following in-game public builds from (for example a Haze build), and I ran into something I’m a bit confused about.

At a certain point, even after getting all core items and picking up some of the optional lategame items, all my item slots were full. I wasn’t really sure what the “correct” next step is at that point.

Is it generally better to:

- Sell some level 1, 2 or 3 items to make room for level 4 items?

- Or keep lower level items if they synergize well with the hero/build, even if that means skipping some higher tier items?

Basically, how do you decide what to replace in the late game once your build is “done”? Any general rules of thumb would be super helpful. Thanks!