Surcharges and Product Availability

Do you have an item whose price and/or supply fluctuates? Of course you do, because we all do. Every business has seasons. Supply goes up and down as does demand for a certain product. I was talking to my mechanic recently and he said that he can count on the fact that at the start of the school year and while the fair is in town, business will be slow. Why those times? He doesn't know, but it happens like clock work every year. These are predictable occurrences, but what about the unpredictable occurrences like the US getting hit by multiple major hurricanes? That's why it's good to have systems in place for both the expected and unexpected. Not just a disaster recovery plan, but a plan for the case when, while demand stays the same, supply is dramatically reduced.

Does you current accounting system or the team behind it help to handle these issues?