First my mother has told me that I can build a house on her land circa 1.5 acres if I wished. It has a small old house on it, but it will have to be knocked.
My uncle is ageing and has a small farm, some sheds etc. it is still in use as farmland. circa 100 acres poor quality farmland, both parties are still alive and well so I'm not inheriting the land.
I had a similar situation with an old cottage my mother owned. I didnt have to pay CAT. My only costs were solicitors fees. Value up to €496,824 is exempt from tax for parent to child. As far as I know you will pay CAT at 20% on value above €24,841 for your uncles property (Minus costs)
But there may be exemptions where farmland/farmers are involved, and on the transfer of property between relatives-it may pay to take professional advice on the issue.