Checking that a necessary item has been purchased

[deviouscow]

Is there a way to link two (or more) products such that if you purchase something from product group 1 you must also purchase something from product group 2?

I want to sell shirt designs and blank shirts off my website - so if a person buys a design I want to ensure they've bought a shirt to go with it.
The only way I know of would be to have all the possible designs as a dropdown selection box when they purchase a shirt. If I end up with say 500 designs though that's not a feasable solution.

So can you link the purchase of one product to the purchase of another?

Thanks!

[Ajeh]

There is nothing built into Zen Cart, at this time, to manage this ...

I am not sure if there are any Add Ons for "have to buy this with this" or not ...

[deviouscow]

I couldn't find any - I was hoping someone on here might have some ideas or know of a module I couldn't find!