Creation of High-Fidelity Science Fiction Spaceship

Modular Sci-Fi Spaceship — Game-Ready 3D Asset (Unity)
Overview
I'm looking for a 3D artist to build a hard sci-fi interstellar colony ship as a game-ready, modular asset for a Unity game. I have a concept render (attached) that defines the look and layout — the job is to rebuild it faithfully as a clean 3D model.
Style
Hard sci-fi / NASA-punk: utilitarian, paneled grey metal, exposed trusses, functional and weathered — no sleek, glossy or fantasy look. The reference image shows exactly the aesthetic I want.
Key requirement — modularity (most important)
The ship must not be one fused mesh. Each module has to be a separate, sensibly named object so I can show/hide, swap and recolor them in the engine:

Spine / truss backbone (core structure)
Command bridge (front)
Cryo / tank bays (the cylinder row)
Water reservoir (the spheres)
Hydroponics dome — with the glass and the interior crop as separate objects (I grow the plants via script, so the dome can be empty or full)
Cargo containers
Reactor + engine block (rear)
Solar panels — each panel its own object (they get added/unfolded as upgrades)

Anything that should move, toggle or change independently must be its own object with a sensibly placed pivot/origin. I'll do the actual animation in Unity — I just need the parts and pivots set up so it's possible.
Technical specs

Game-ready, real-time optimized. Low-to-mid poly (rough target under ~40–60k triangles total, open to discussion).
Clean topology, no unnecessary n-gons.
PBR textures (albedo, normal, metallic/roughness), separate materials per module. An emission map for the lit windows/strips is a plus.
Model centered at origin, real-world-ish scale, consistent units.
Clear, consistent object/material naming (e.g. Mod_Bridge, Mod_HydroDome_Glass, Mod_HydroDome_Crop, Mod_SolarPanel_01).

Deliverables

Source file (.blend preferred)
Exported GLB and/or FBX, Unity-ready
All textures/maps

Exterior only — no interior modeling and no animations needed at this stage, but built modular as described above.
Please share a portfolio with hard-surface / sci-fi work, an estimated timeline, and a quote. Reference image attached.