Personally, I live in a border town and purchased an undervalued house in Northern Ireland at the end of last year - I know it was undervalued because there was two bank valuations done, both resulting in higher valuations than what I paid.
Since then, house prices have risen a little in Northern Ireland and I'd been considering selling the Northern Ireland property to fund both a rental property and a PPR in the Republic of Ireland.
The CGT and DIRT rates in the Republic are a significant factor in me reconsidering these plans, in addition to the significantly lower mortgage interest rate I'm on when compared to the Republic's best buy rates.
In Northern Ireland, an ISA can be used to purchase shares/funds up to the value of £11,520 per year, rising with inflation. The shares/funds within the ISA will be except from CGT. Also, you can use up to half the annual allowance for cash deposits, the returns from which, are tax-free.
In addition, you have an annual exception from CGT for gains of up to £10,900 outside the ISA. This compares to €1,270 in Ireland.
With this in mind, I'm seriously considering holding off on plans of moving back to the Republic of Ireland.