Around 5,000 on my current character. I make lots of chems and grenades but I also use them (and I buy fertilizer), and I pretty much tend to buy a lot of unique weapons and armors even if I don't use them, just because.
I also don't abuse of the industrial purifier thing.
I do hoard a lot of junk so I guess if I went out and sold everything I had in the workshop that number would go pretty high.
I also keep all the pre-war money and gold bars in a safe, also just because. That boosts my total I guess.