How to apply a discount based on the delivery date ?

[@lexandre]

For ski rental.
How is it possible to apply a reduction, not on the date of order, but according to the delivery time?
Thanks

[PolishedGeek]

Can you give us more detail about how the delivery times will work in your store?  Will there be timeslots / time ranges in a drop down custom field? If so, then you can do this as a cart variant.

[@lexandre]

Thank you for your answer.
In fact, the client selects the first day of skiing, selects his material (with discount applied for the period of skiing), places his order. The following equipment is booked and the customer only has to come and take his equipment in the shop for his first day of skiing. There is therefore no real deadline. The objective is to apply a discount based on the rental period and not in terms of time or the customer places his order.
For example (french website) : http://www.skilou.com/

[@lexandre]

For Joomla 1.5 & Virtuemart 1.1 if possible.
Thanks

[jenkinhill]

??   http://forum.virtuemart.net/index.php?topic=106866.0

[@lexandre]

OK Jenkinhill 
If you have the answer for Joomla 2.5 and Virtuemart 2 I'm interested.

[@lexandre]

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