Need help tweaking Travelo hotel booking theme

General information for the website: We are building a hotel booking page and use Travelo theme
Kind of development: Customization of existing website
Description of requirements/features: Travelo is a hotel booking theme for Wordpress. You can check at http://www.soaptheme.net/wordpress/travelo/.

For every hotel there is a search form for rooms in the description area. You can see on this page, for example, when clicking on the availability tab: http://www.soaptheme.net/wordpress/travelo/accommodation/foscari-palace/

As you see the customer must select Check In and Check Out dates.

In Hotels settings in the backend there is one setting which is called "Minimum Stay Info", where you set the minimum amount of days to be booked. When you select a Check Out date resulting in less than the minimun amout of days, then you get an error message. You can see this setting in the theme documentation here (scroll little down to the following accomodation settings): http://soaptheme.net/document/travelo-wp/#main_features

What we need is also a "Maximum Stay Info" field, which (similarly to the Minimum Stay Info) gives an error when selecting dates which exceed the Maximum Stay Info value.

We need this because we mostly have fixed package prices for a certain amount of days, which means that customer can book lets say three days for a special price. This special price is for exactly three days only, not more and not less.

We asked the theme developers and they said: "You can add a field accommodation edit panel to set maximum stay and change search algorithm a bit as your need."

I will send you the complete theme for the developing period. It of course may not be used otherwise.

Please only make offers for the whole job (including bug fixes) with time estimation. And only make offers if you really know Wordpress code pretty well. Thank you an looking forward working with you.
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