50 years I think puts here them highly in danger zone... That means 1970s... Which have whole host of very well known issues. Now 100 or even 70 year old houses... If not ruined in 70s-90s by renovation...
Fair enough - but point still stands, newer is not always better (to me). Give me a house that is still standing decades after mother nature threw everything it could at it, over a shiny new one any day.