Custom Form Fields

Site URL: https://www.kepridgestorage.co.nz/

Hi,

Ideally we'd like our customers to be able to click the "add to cart" button, which then triggers a custom form to come up.

Here the customer would fill out two dates (pick up / drop off), and we'd automatically calculate the number of calender months selected (e.g. from 20th July - 3rd Sept would be 3 months).

The number of calender months would equal the quantity (as we charge per calender month) so this would then add that quantity to cart.

Those dates woud also be stored somewhere so that infomation is passed to us after checkout.

Anyone have any ideas on how this could work?