Last year for BAKUC I experimented with the concept of adding a silver underlay to the model which ended up being used by Kenji and Sok for BAKUC. The silver underlay would be used as a metallic layer for express battle damage. However as they were under time constraints the model wasn't scarred as planned. I have adopted the method now for a model of my own, The HGUC Gouf Custom! I wasn't planning to do battle damage at first until I saw the box art... however I went overboard with my one LOL!
I started to appreciate the concept of pre assembling certain parts recently I found that I could really save on paint from doin this. Okay the below shots highlight the silver underlay afterwards the colour gets sprayed on. so each piece gets three coats a grey undecoat, a silver underlay and a colour layer.