Two Oregon Real Estate Law Questions

[Tayler Monigold]

Looking to purchase my first house hacking deal in Southern Oregon thanks to the encouragement from this podcast and community!! The properties I've found have both units already rented under existing leases. Does anyone out there know if I can legally take over a unit/break someones existing lease due to the new ownership?

Second question: I want to buy this duplex as my primary residence. Does anyone know the minimum amount of time I need to live there before renting the unit I will occupy? 

Thank you in advance!