I use Wave instead of Quickbooks. Its free and works well for me.

I’ve created a simple inventory tracking solution you can find at AlpacaTrack.com. I made it when I was having a hard time finding a reasonably priced solution for my hobby projects.

I think some sort of visual inventory is probably best for consumable type items such as office supplies. In a previous manufacturing life we had bins of parts, and if someone used up the first bin there was a card at the bottom/back of the bin that you tossed in a basket to be re-ordered.

If you are looking for a tracking system I’ve created a simple system for cases such as these. You can see it at AlpacaTrack.com. Though you still need some sort of notification/manual entry when the office supplies are consumed.