conditional aggregation

I need help to work out the formula I need for my project.

I have two worksheets. See attached.

On Nikkis Working worksheet I have recorded all my data. In columns M&N I have the dates and amounts of deposits paid. In columns T&U I have the dates and amounts of invoices paid.

I am currently using the following formula to work out how many quotes and invoices are processed each month. This is for the quotes accepted in Dec 2010.
=SUMPRODUCT(--(MONTH('Nikkis Working'!M2:M1142)=MONTH(A20)),--(YEAR('Nikkis Working'!M2:M1142)=YEAR(A20)),--('Nikkis Working'!B2:B1142="Accepted"))

I need to find the formula to have the amounts for the Deposits Paid for the Month and Invoices Paid for the month. Thank you in advance.

Nikkis Working.JPG
Nikki Critical data.jpg