I bought a pre-assembled model I found at Otachu Akihabara Store No. 4 and painted it in parts.
Removing the gate marks and re-carving the existing mold was a lot of work, but I'm happy with the cool finish!
The main body is a two-tone color with the molded pink and partially painted azuki bean, while the railgun and machine gun have less color separation and are painted in light gunmetal to give them a more substantial feel.
Removing the gate marks
Removing the parting lines

HG Gundam Flauros | あきんこ's Gunpla works