I paid € 6,863 for UFH materials and labour upstairs and downstairs in the same size house as yours. I bought Polytherm materials and my plumbers did the installation as part of the overall plumbing package. I ended up not going with a ground source heat pump but would have gone with Dunstar ([broken link removed]) in Cork if I was selecting a provider, well established for many years, organised a visit to an existing user for me and knowledgable people in general I thought anyway.