Tenants necessary?

[Matt Blutowski]

I'm looking at my first properties, and have been cautioned by a friend to avoid a duplex that looks good because it does not have a rental history.

A granny owned the duplex, and since she died one of her adult grandchildren has been occupying the property, leaving the upstairs vacant.

My general question is, do you look suspiciously at vacancies, or disregard them if you find suitable reasons for the vacancy??