Yes, you have to pay it, as legally the executor of the estate will be the owner of the house once the will is probated. Even if the executor will be presumably transfering ownership of the house over to a beneficary of the will, or selling it on their behalf, the nppr tax still has to be paid as the house is not the principal private residence of the executor.
(This is a fairly new tax so that Revenue can get a few more bob off people with holiday homes and rental investment properties. The tax is payable to the local authority. It is a crazy set up that Revenue treat people who are just acting as an executor of an estate the same as those with a holiday home. But that's Ireland for ya !)
Anyway, the tax should be paid from the funds in the estate, as it is a legitimate executor expense. You should not be personally out of pocket for it. March 31st is the date that the tax is due by each year. However, your liability to pay starts when the will is probated. I'd advise you to pay it as soon as possible after that, as you are charged a late fee of 20e for each month that you don't pay after you become liable, in addition to the 200e tax itself. I found this out the hard way last year. I inheirited a house close to the March 31st deadline. I sold it 8 months later. I only found out about the existence of the nppr tax when the solicitor wanted proof that it was paid. Not only did I have to pay it, I had to pony up at additional 160e in late fees for the 8 months that I was late in paying it.
There is no way around paying it. If you are using a solicitor to sell the house or transfer it to the new owners, he will not do so unless you can show him your receipt for paying the nppr tax, as he can get in trouble for handing a sale/property transfer of a house that all the taxes were not paid on.
You can pay the tax and get a lot more info at
http://www.nppr.ie