Best practices for raising rent

[Daniel O'Donohue]

I found a duplex in a great area of Northern California that is currently for sale and being rented very low (1 unit $2,000/month and 1 unit $1,900/month. I know that area really well and know that I could be getting $3,300-$3,500 per unit.

What is the best way a buyer can raise rents to market value? Are there any CA laws that restrict me from doing so?

Thanks!