Fast Secure Wordpress plugin adjustments jQuery

General information for the business: Campervan hire New Zealand small company
Description of requirements/functionality: Using Fast Secure​ contact form (WP-plugin) looking for someone who can make date ​-​range​ ​input dependable on our forms. Once the ​ ​1st

date is set, the​ 2nd ​ calendar​ pop-up ​ must open at least one day after the pick-up date, this to prevent the drop off date to be set before the pick-up date.


I think Fast Secure contact form is using jQuery; the select date range code is available here: http://jqueryui.com/datepicker/#date-range just don't know how to implement it.

Needs to​ know how to adjust more than one ​ forms on the website and easy to install on ​another website as well. See ‘get your free quote’ form on www.campervan-hire-new-zealand.com for better understanding.
Extra notes:

new posts are only visible on the homepage ( we did a setup so the 2 newest are always on homepage) but they not showing in the category we added them to.