4-Plex --> Duplex Conversion Experience in H-Town?

[Ian Schimmel]

I'm looking to connect with someone who has had experience converting a 4-unit multi-family building to a duplex. 

I currently have a 4-plex property that would be better utilized as a side-by-side duplex. The plan would be to combine the first and second floor units on the left side of the building to form one upstairs/downstairs dwelling, and then do the same on the right side of the building. This would allow us to have two "side-by-side" dwellings that share one wall running down the middle. (My family plans to live in one side as a house-hack method and we'll rent out the other side.)

I've learned that there are fewer obstacles to scaling multi-family buildings down in unit size (vs. up). But I've also been down to COH and discovered there's a catch: the "4-plex --> duplex" plan above would require us to completely replace the shared wall between the two dwellings with a firewall. According to COH, this conversion process would also trigger a general life-safety inspection, and potentially the need to bring the entire building up to 2024 code (at least in terms of safety issues: electrical, stairway tread width, etc.) 

Has anyone had experience with a project like this or have any contractors or designers to recommend? Looking to learn more. Thanks!