put and set up minimum purchase for different shopper groups

[FraArc]

Hi,

I have two problems... First I use Joomla 2.5.17 and VM 2.026d

question nr. 1

there is a way to put a minimum purchase (in value) for a shopper group (ex. 300 € for wholesaler)?

question nr. 2

Is it possible put a minimum quantity of purchase and the interval of quantity for different shopper groups?
for example: a default user have a minimum of quantity of 1 product, the wholesaler has a minimum of quantity of 5 products and an interval of quantity of 3 products.
Put the minimum of quantity into "Interval of quantity" in the price configuration of products is not a solution because the wholesaler cannot see the right price until the wholesaler does not add 5 items into shopping cart...

How I can set up these quantitative?

Hoping for your help thanks at lot for your replies
Francesca