Buying Multi-family and Increasing Rent?

[Jesse Kailahi]

I've been looking at multi-families, and few ever get close to cash flowing with my specific circumstances, but there are some properties that could work... but only if the rents were increased. So I was wondering how you would go about increasing rent for units that are far below the average rent for the area. 

Sacramento has no rent control, so theoretically you could bump the rent up to any amount as long as the tenant was month-to-month and gave 60 days notice.

If the tenant was on a lease, then you would have to essentially give 60 days notice, 60 days before the lease was to end.

So, if the rents are far below market, but the property is priced appropriately for the area based on comps, are you able to take any action as an investor to make it work? 

Are you able to sign new lease agreements upon purchasing the property? 

Are you able to receive the current lease agreements from the seller to get a feel for when the lease is ending? 

Any anything wrong with increasing rents by 50% or more (beyond the moral dilemma with increasing rents for LONG term, established tenants, like a 90 year-old g-ma)? 

Thanks!