In your BOB you may or may not have a barter bag.
I like to have one because I have seen what happens when something goes wrong and people panic. Flooding to gas pumps and grocery stores and fighting over things like bread. If you are too late you will need to barter with someone for what you need by having something they need or want.
Water purification tablets
Anti- diarrhea tablets
Those are some ideas
Depending on the situation you may find that some items become more valuable.
- 10 of the Best Bartering Items if the grid goes down (thesurvivalplaceblog.com)