Buying house and increasing rent for tenants?

[Vince N.]

I'm considering a duplex that has both units filled with m2m tenants. Each unit is paying about $200 under market rent. 

What are your guys thoughts on increasing rent as soon as I make the purchase? I don't mind if the tenants leave, but I'm worried about them vandalizing the property if they do. This is in a B area so its probably not a realistic concern but its my first property so I'm a little weary. 

Are there any other considerations?

Thank you!