add gift subscription personal message on checkout page

can this be done? if yes, how?

1) add simple input field for a gift message
2) only on checkout page
3) only for specific product
4) only per product (as in if you bought 2 gift subscription, each recipient gets a personal message)
5) placement of input field needs to be right under product row? (not just anywhere on the checkout page)
6) easily add this message to the auto emails that are sent out

thanks

PS. the Product Add-On plugin, can’t do checkout page