Rookie Q: How old is TOO old?

[Bronson Simmons]

I have noticed a few MFU here in Louisville that check some criteria, but are quite old. Some were built in 1900-1920s. I know maintenance is worse in old buildings, but how old is TOO old? What age or year built is too old for you and why? I'm afraid of drawing the short straw of being stuck with a crumbling building that needs rebuilt to the foundation and not having the money to do so. Is that even a realistic concern?