Excel formula based on date variables

I'm trying to create a fee calculator but I can't seem to get the formulas to work for me. I'm essentially trying to write one long formula that takes into account all of the different date variables. I have six selectable products and I've been trying to use a combination of IF, AND and OR statements.

My columns are set up like this:

List of products:

Product 1

Product 2

Product 3

Product 4

Product 5

Product 6

I want the formula in C2 to retu:

"No" under "Fee Payable" for the following:

• IF Product 5 or Product 6 are in A2, OR
• IF Product 3 OR 4 are in A2 AND the date in B2 is less than 18/12/2014, OR
• IF there is any product in A2 AND the date in B2 is less that 29/03/2012

"Yes" for the following:

• IF Products 3 or 4 are in A2 AND IF B2 is greater than or equal to 18/12/2014, OR
• IF Products 1 or 2 are in A2 AND IF B2 is greater than or equal to 29/03/2012

I would like C2 remain blank until something is entered into A2.