The Revenue Ready Reckoner (http://www.revenue.ie/en/corporate/information-about-revenue/statistics/ready-reckoner/index.aspx, on page 18) shows the effect of a 0.5% increase in the Stamp Duty rate on non-residential property (€47m). This is multiplied up to €94m for a 1% increase, or €376m for a 4% increase.
I am informed by Revenue that the estimated yield from the increase in Stamp Duty on non-residential property as announced in Budget 2018 measure is based on payments of Stamp Duty on the purchase of non-residential property in 2016 and an assessment of trends in payments in 2017. In the absence of any other forecast of transaction levels in the non-residential property market in 2018, trends from recent years provide the only reasonable basis on which to estimate future receipts. The estimated yield makes an assumption of no behavioural change.