Where can I get a statement of fees (detailing charged fees for a specific period)?

Transaction reports can be generated based on your needs from the application (eg. weekly, monthly). Just go to the sales tab and select the period you want and click "Download transactions". The transaction report will contain the fees for each transaction.

You will also get daily payout reports via email, detailing all the transactions and the associated fees for the batch of funds being paid out. You will be able to download these from within the Sales tab as well.