Q: apple id balance

if the balance doesn't cover the entire cost yes.

if they are free, no, you just need an active account.

if you need to set up an account without a credit card see this docuemnt

Create an iTunes Store, App Store, or iBooks Store account without a credit card or other payment method - Apple Suppor…

Not necessarily. If your balance covers the total price of the item (i.e. including any applicable taxes) you shouldn't need a card on your account (unless this is the first purchase on the account, in which case it will depend upon how you created it) - a family organiser cannot use a balance.