Realistic North Carolina Role-Play Map

I need a fully explorable, North-Carolina–inspired role-play map for a video game project my group is developing. The brief calls for a believable open environment that blends rural and suburban areas and feels authentic down to the street signs. Reference sketches, dimensions, and location notes are all gathered in this shared document:
https://docs.google.com/document/d/1FDXIkUSbDyvcFZjl4cOyc4PBwWEfnrGKXtKC_dtIdkY/edit?usp=sharing

Scope highlights
• Terrain: rolling Piedmont topography, rivers, and coastal-plain marsh edges, all textured with realistic foliage and ground materials.
• Infrastructure: DOT-style two-lane highways, county roads, and neighborhood streets with accurate lane widths, markings, traffic lights, sidewalks, and signage.
• Buildings: a mix of homes, municipal structures, diners, gas stations, and small businesses. Exteriors must be highly detailed; key landmarks should include partial walkable interiors for role-play (lobbies, shop floors, jail cells, etc.).
• Performance: final assets should stream efficiently in-game without noticeable pop-in on current-gen PCs.
• File delivery: the entire scene packed and ready to import into the engine we ultimately decide on together (Unreal, Unity, or another you recommend), with organized layers, LODs, and a README explaining folder structure and material instances.

Acceptance criteria
1. Streets, signage, and building styles match the reference guide and North Carolina code where provided.
2. Day-night cycle and basic weather variations function correctly on delivery.
3. Average FPS remains above 60 on a mid-range GPU at 1080p in a populated test scene.
4. All textures and models are original or fully licensed for commercial use.

If this type of large-scale, realism-focused environment is your specialty, let’s discuss your proposed workflow and timeline so we can bring this map to life.