The first monitor is the easy call. Clipped to the Tool Cupboard, it puts the upkeep on your phone, and that is worth more than any box it could watch. The second and the third need a reason, because each takes a piece of tech trash that a C4 or a sight was waiting for.
A monitor on a box becomes a tripwire only once its pulse reaches a smart alarm, and the alarm takes tech trash too. So a watched box costs a whole C4's worth of circuitry: fair for the box of rockets, rarely for the box of wood.
Decide where it will hang before you craft. Its own text names only the cupboard and the large wood box, so put a large box where you want eyes instead of counting on whatever chest your loot happens to sit in.
Questions
Storage Monitor ×10: how many resources?
High Quality Metal ×30, Tech Trash ×10.
Which workbench does Storage Monitor need?
Workbench level 2.
How long does Storage Monitor take to craft?
25 s for one, every step included.
How much scrap does researching Storage Monitor take?
