Personalisation charge

[hawkan]

We have a product that you can order between 1 and 5000 units.
The price depends on the quantity ordered (the more you order the cheaper the price pro rata).
Regardless of quantity ordered there is a one off design fee, although we have set the product price so that the correct price is charged per amount ordered (eg, if you add 500 of these items to the basket it charges the correct price for 500 units BUT it also adds 500 design fees when we only want it to add one regardless of the number of units ordered.
Any ideas as to how we just get it to add the one design fee irrespective of quantity added to basket would be greatly appreciated.

[jont]

I had a similar situation a few months back .... at the time it was a toss up between having a second product beneath for the cost of plate set-up or building the cost of the plate into the product - the latter made the cost of just 1 product appear to be very expensive and psychologically tuned people away so resorted to having a separate product beneath for the personalisation (personalisation was an optional extra).

If anyone has an alternative I would also be interested.