Egress windows - Absolute requirement?

[Jake Boyer]

Hey All, I've got a duplex where we've got a full height basement that we'd like to add two bedrooms and a bathroom to. The basements (one on each side) do have windows currently, but they wouldn't qualify for egress windows for bedrooms due to their height off the floor. Excavation and cutting into the foundation wall would not be cheap for the egress windows and we're up against it on the budget. 

I'm not expecting this to be much of a cash out refi potential on this property so my main goal is to increase cashflow as much as possible. I'd like to use the basement as additional bedrooms and could still add the bathroom since there is existing plumbing already, but the expense of egress windows and getting someone to do it in a timely manner is damn near impossible. I could easily frame the walls up and add closets, electrical outlets and HVAC ducts. I see people using basement rooms as bedrooms that don't legally qualify all the time, so I'm wondering what the concerns/liabilities are? As a landlord, you wouldn't tell someone that they can't set up a bed and have a member of the family sleep in the basement, so does this create any liability for the property owner? Could I list it as a 4 bed duplex legally? Illegally? Any concern there? Cashflow as a 4/2 on each side would be so much stronger than as 2/1's but not enough to justify the expense to do it all above board. Open to any and all feedback, please!