How to value closing inventory in construction contracting

Ascertain the closing stock statement.& stock register (if maintained) Find out the last purchase of each item. Obtain the purchase invoice & note the price on which the firm has purchased. it alone will the fair value assuming purchases made earlier has been consumed. If the stock register is available it's fine since it gives you a date of purchase, values & all required details.

Thanks Dear, but Its normal Closing stock procedure for trading company. I asked for construction contracts valuation of work in progress.