Create a table of all the valid denominations. One field:
DenominationID Currency primary key
Save as (say) tblDenomination.
Now you need a transaction table. Fields:
TransactionID AutoNumber primary key
ClientID Number relates to your
tblClient.ClientID
TransactionDate Date/Time when this transaction took place.
...
One transaction consists of multiple denominations, so you also need a
TransactionDetail table with fields:
TransactionID Number which transaction this row belongs
to.
Quantity Number How many of this denomination
DenominationID Currency Which denomination.
To get the value of the transaction, create a query, and type an expression
into the field row:
Amount: [Quantity] * [DenominationID]
When you sum this field (in the footer of your form or report), you get the
total of the transaction.
Note that the calculated total is *not* stored in the table. If that sounds
strange, open the Orders form in Northwind sample database that installs
with Access.The rows of the order are calculated in the subform, and shown
on the main form without being stored anywhere. That is the right way to
design a database.