Enable / Disable List based on Independent Cell

Hello,

I am building a template using excel 2013 and I would like to enable/disable a list and allow free form entry in a cell based on the selection from an independent cell.

For example, Cell A1 has a "Y" or "N" list enabled.

If "Y" is selected, I want to enable a restricted drop down list in cell B2 (with options of $0.00 or $10.00 for example).

If "N" is selected I want users to be able to input any dollar amount they choose in B2.

Is this possible? Any help is greatly appreciated!

Thank you!

Thanks FDibbins, is there a way to keep the STOP error intact for the list, but allow for free form entry with a "N" selection in cell A1?