Selling 2nd home+not paid NPPR.

My girlfriend is hoping to sell her other house in the near future but hasnt paid the second home tax yet.So,we're wondering does she have to prove that this is paid before selling?Will estate agent or solicitors look for proof if its a local council tax?
Also if she does have to pay it,how much will it cost her including late payment penalties?Thanks

Any good solicitor should look for proof of payment. From what i can remember it is something like an extra 20 euro per month for late payment. Go to www.nppr.ie for more info.

Thanks bessa,i'll pass that on to her