Hi Tubbs,
If it's any help, as you referred to I wrote previous similar post. On advice I got there, I talked to our surveyer and he said it was normal to ask for money off to do things that are going to add up to a reasonable amount.
Ours is slightly different in that overall our place is fine but the few things could add up...for us we're probably going to seek some money off as contribution to the costs...in your case it would seem very obvious that the work will need to done so your offer price didnt anticipate extra €10,000.
best of luck...