ABC is a reseller of goods. The following transactions took place during March for ABC as it pertains to inventory:

March $1$ Inventory Balance of $200$ units purchased at $$20/$Unit

March $7$ Purchased $200$ units at $$22/$Unit

March $10$ Sold $300$ units at a price of $$40/$Unit

March $15$ Purchased $100$ units at $$23/$Unit

March $21$ Sold $150$ units at a price of $$40/$Unit

March $25$ Purchased $100$ units at $$24/$Unit

What is the COGS for the month of March assuming the company is using the Perpetual $-$ FIFO methodology for inventory valuation?