What do you mean by 'purchase value'?
Purchase value is the price you paid for an item when you bought it brand new. The purchase value of all your belongings summed up together determine your 'coverage', which is the maximum amount you can be reimbursed if the item(s) is/are damaged or destroyed.
Note, that the amount you receive can be less, if the new market price of the item decreases. Nevertheless, we make sure you replace whatever item with one that is identical or equally as good.