RowNumber() and SUM() in one query

is there some way who to get last record using rownumber() and SUM of one field (money in this case)? I've tried to come up with a query like:

SELECT 
        [date]
        ,...
    FROM
        (
        SELECT
             CAST(t.timestamp AS DATE)              AS [date]
            ,.../some fields/
            ,row_number() over (partition by ca.logical_number order by t.timestamp DESC) as rownumber --last update(record) transaction
            --,amount_transferred = 
            --(
            --  SELECT
            --      ,SUM(t.money_value)     AS  amount_transferred
            --   FROM
            --      TO_Transaction t
            --  GROUP BY
            --      CAST(t.timestamp AS Date)
            --)

        ) AS t
    WHERE rownumber=1

What the query is supposed to do is to find current purse balance and all money transferred during a day. Any help would be aprreciated. Thanks.