Using one stock level for multiple products

-- HikaShop version -- : 2.3.2
-- Joomla version -- : 3.3.3

In my shop I have multiple products (tickets)
1 adult: € 20,-
2 child: € 15,-
group: € 50,- (minimum of 4 tickets)

Because I'm selling seats, Is there a hack to create these individual products but use one stock level? Unfortunately They all have there own discount so it's not possible to create child products and use one stock this way....

Hello,
The solution will probably be to use a "Type of tickets" characteristic and use different price regarding the quantity of product added to your cart.

I'll try that!

Thank you!