It was remade several times to utilize the new knowledge and methods I came up with while working on it. Tips I invented during my work:
1. CAD-like workflow in Blender: I made every curvy surface with bevel modifiers, so I can control the amount of edges on them to create both HP and LP with the same base mesh.
2. Heavy use of Instancing: I used same base mesh for HP and LP, so when I do changes in the model, they are reflected in both versions simultaneously. The only difference between instances was the assigned modifiers.
3. HP beveling with Remesh + Smooth: Instead of adjusting mesh to make HP bevel work fine on every edge, I just added Remesh + Smooth modifiers on HP mesh instance.
4. Booleans: Initially, almost everything was made with booleans. However, while working on LP I applied the needed ones, while those which will be only on HP stayed as modifiers.