Give every item a job
Separate inventory into working ingredients, near-term order items and upgrade materials. Anything outside those groups is a candidate for sale. This prevents rare-looking items from occupying space without a plan.
Upgrade one target at a time
Expansion materials accumulate unevenly. Pick the barn or silo as the current target, keep the required sets for it and sell genuine surplus. Trying to finish every expansion simultaneously creates gridlock.
Use the roadside shop as overflow
List common crops and products at sensible prices instead of discarding them. Keep at least one free slot when harvesting or collecting from machines so production does not stop unexpectedly.