[Typo3-shop] Extra input field in listview

[Jogvan Olsen]

For some of my products I need an extra input field in Listview and 
Singleview, so the buyer can type in some extra information (car make and 
model).

Is it possibly to use 'Color (Variant 1)', 'Size (Variant 2)' or 'Gradings 
(Variant 4)' for that purpose?

And if it possibly - how can it be done?

Thanks in advance
Jogvan Olsen