How does building age affect underwriting?

[Trevor J Dammon]

I'm looking to begin my investing journey with an owner occupied duplex. I'm looking in the Minneapolis area. My plan is eventually to move out and keep the duplex as a REI. One thing I have noticed is that most of the buildings in the city are 100-120 years old. Does the age of a building matter much when creating a real estate plan or can I ignore the building age if the HVAC, roof, and foundation are all much newer. If I hold for 30+ years I could end up with a property that is 150 years old. My fear is that at this age buildings will lose value even if renovations and repairs are up to date.