Plumber and Company has a fleet of motor vans used for making deliveries to customers.

The owners want to show these vans on the statement of financial position at their current values rather than at their historic cost. They would like to use either current replacement cost (based on how much would have to be paid to buy vans of a similar type and condition)

or current realisable value (based on how much a motor van dealer would pay for the vans, if Plumber and Company sold them).

Why is the choice between the two current valuation methods important? Why would both current valuation methods present problems in establishing reliable values?