Advice on buying with tenents

[Stephan Guna]

So quick questions guys I have somewhat of a situation in which I would like some advice. So just some notes this would be my first investment property. I been looking at houses for awhile now and recently found this duplex(multi-family) nearby which I liked a lot and seems like a solid investment opportunity. However, I learned that there are currently two tenants living there who are paying $650 a month each, which in this area is pretty low. If I kept these rents, I would barely break-even. 

Also, I noticed the lease is only month-month, so do you guys think it would be a good plan to buy the house and then increase rents as soon as I am able to. I plan to increase to $850-900 each to make some profit. Also, what are some contingencies if go with this particular plan(How fast am I able to implement after closing? Etc?