new property eviction

[Jason Dillon]

I am looking at a 2 family property that has a lot of potential in a good area.  Both units are rented and need some work.  Both tenants are on a month to month agreement with the current owner.  If I buy this property and there is no lease how easy/difficult would it be to either drastically change rent or evict?  The rents are way under market value and tenants have been there for 14 yrs and 3 yrs.