How do I change a property from a single family dwelling to 4 units in a RM1 zoned

[Deepak Pakala]

Hello Biggerpockets!

The property I'm interested in is the layout as a duplex but I can turn it into a 4plex by changing the layout around and adding walls, 2 Kitchens, and a bathroom on the title it is a single-family dwelling but how do I turn this into 4 units legally so I'm able to cash out refi. Also What are some hurdles I can be facing? I'm using a hard money lender just an FYI, 2000sq turning it into Three 1beds, One 2beds. Would I need an engineer, architect, pull permits? Is this too much work?  

Thank you