user choose price?

I'm creating a flower shop.
For some of the the products I use characteristics to make a difference between the size of the bouquet

Now I would also like to have the possibility to let the customer choose a price. e.g. roses are €2 a piece, €20 for a medium bouquet, €40 for a large bouquet. under these prices I would like to have a blank field where the user fills in an amount.

is this possible?

That would require to create a custom field of the table "item" so that there is this field, plus a quantity price calculation override plugin so that the system uses that price when relevant. We have some documentation for developers regarding that here:
www.hikashop.com/en/support/documentatio...r-documentation.html

Thanks, I will take a look into that.