Single Family to Duplex Conversion. Electrical Question

[Logan Pourbaix]

I'm looking at a deal where a single family home can easily be converted to a duplex. Everything checks out. The Zoning is there, minimal reframing etc. My question is in regards to the electrical. Of course I would have to get my local EMC to set a new service for the additional unit, but what about interior wiring. 95% of all the walls/sheetrock are in good shape. obviously Ill need a new panel and each unit's wiring needs to be independent of each other. I hate to take down the sheetrock to the studs just to rewire. Any recommendations or anyone ever did a similar project? What did you do? Single store on a slab.