Forced product quantity

[big_garryb]

Hi all,
I wish to run a special offer - if the customer buys 10 boxes, they will get the 11th box for £1.

i was going to set this up as a seperate product category. i would like to force the quantity of 10 (20,30??) with maybe a tick box for adding your extra box at £1.

Woulod this be possible, or can anyone think of a better way to do this!?!?!

Thanks,
garryb

[cdicken]

The only way I can think of to do this is to create a component called 'Selection' with an attribute within it called 'Quantity'. The choices are '10 (+1 free)', '20 (+ 2 free)' and '30 (+3 free)'. You can then set the prices within the 'Permutations' tab of the 'Selection' component so that each selection will cause the correct amount of money to be charged.