Adding and removing extra pages

I have a quote template setup for our companies use on the field. This allows
our sales team to have a standard quoting system for our products. What I
need to do is provide the user the option with a check box click to include
or exclude a notes section.
if the user Selects NO the printed quote will not have the extra blank page
attached. If the user selects Yes another page is shown where the user can
enter notes and print.

Please let me know how this can be achieved.

Thanks,

Marcus