An update:
I went ahead with a survey from Fox and Gallagher as mentioned above. Structural engineer called Des came out and did a very thorough survey.
He spent a a good hour inspecting the house and confirmed all of the issues I had already seen, plus a few more I had not seen.
He gave me some insight into a planning issue which I was concerned about.
He was good enough not to mind me being there asking him questions during the survey.
He gave me a verbal summary of the main issues that evening, and a written report a few days later as agreed (2 hard copies with many colour photos, plus soft copy).
Overall, his report and comments were enough to justify a reduction of price, but as the vendor wouldn't budge, I ended up buying another house.
I was happy to get him to do the survey for that one as well.
I think in each case it was good value (but not too cheap!) at 300 euro incl vat, and the level of inspection carried out was more than adequate.
Maybe 300 seems worryingly cheap if you are in Dublin but that's what I paid and it was fine for me.