Double-entry bookkeeping 2: books of prime entry, accounting systems
. Purchase invoices record the amounts owed to suppliers for goods and services supplied on credit.

. The total amount owed to a supplier is made up of the cost of goods and services supplied plus any sales taxes.

. Cash paid represents costs incurred.

. Cash refunds represent cancelled purchases.

. The total amounts listed on purchase invoices – the total amounts listed on credit notes records the total expenses incurred by an entity during an accounting period..

. Credit notes show the total amount (purchases value + sales taxes) that is no longer owed to a supplier.