[TYPO3-shop] checkout requirement: minimum weight in basket

[Heiko Hänsge]

Hello,

we have the following checkout requirements:
- a customer needs to have a overall minimum product weight of 3kg in 
the basket to be able to checkout, otherwise a message needs to be shown
- if there is less than 10kg of weight in the basket, shipping costs of 
7€ should be applied on checkout
- if there is 10kg or more in the basket, NO shipping costs should be 
applied on checkout

As I couldn't find an appropriate hint in the manual to solve this I'd 
like to ask here: Is it possible to do this with tt_products?
And - if yes - how to declare the TypoScript needed? Thanks in advance!

Regards
Heiko Hänsge