Hi,
HikaShop allows (out of the box) to set up the minimum and the maximum quantity of a product in the cart.
There is no feature for this rule (out of the box) but it is possible to implement a little plugin which would interact with the cart when a product is added or updated.
Regards,
Jerome
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.