The scenario, as you paint it, is not possible and I have this on good authority from an employee of the romanian revenue who I know out here and spoke to about this issue today.
The fact is that an Irish company can't just buy a house (least of all the land on which it stands) and pay the VAT or not pay it.
You have two options:-
(1) The Irish company appoints a romanian citizen with an address in Romania to be it's 'fiscal representative' in Romania. That individual goes to the revenue and obtains a VAT number on behalf of the company. Under a special set of taxation rules called 'taxare inversa' the Irish company doesn't pay VAT in Romania on the purchase of a fixed asset, such as a property. The Irish company must maintain a copy of all documents, deeds, contract of sale and any rental agreements etc, etc at the address of the romanian fiscal representative for the time period in which it owns the property. Obviously there is a cost attached to this in paying the romanian representative for his/her services.
(2) You establish a Romanian company and purchase the property through it. This romanian company still doesn't pay any VAT under the 'taxare inversa' provision (which incidentally also applies to around 3% of goods such as scrap metal, timber etc) . Obviously there are also costs in setting up the company and it TOO must have a registered place of business.
The cheapest way to do it is probably option one but there are other considerations which you need to factor in.
Whatever variant from the above you choose there will be taxes to be paid to the town hall on the land and the buildings each year. If you've just bought it and locked the door then probably the fiscal representative can pay these for you.
If, however, you rent the property to a third party, then you will be issuing them with an invoice for the rent each month plus VAT. You will probably have expenses which you can claim against rent received etc. In this case you will also need to employ an accountant.
Basically the scenario as you seem to be thinking about it is NOT possible.