Idea of the costs for opening a hostel

Hello there
I've in mind to open a new hostel in west Europe, probably Portugal. I really don't know anything about the costs for buildings or like to buy a old building and then work on it and renew it.
I know it's a generic information what I'm asking, and everything depends from the size of the building, place etc.. But I'd like to know and I've an idea, of what are the costs to open let's say a small hostel, buying a new building or starting also from 0 and do all the works.
Cheers
Marco