I painted an entry-level model that I assembled a while ago for a "Gunpla Photography Course" in Real Type colors.
The base is spray paint. I used Mr. Color dark green (Nakajima type), light grayish white (Mitsubishi type), and azuki bean. I dry brushed smoke gray on top of the gray parts, black, and white on top of the red parts. I then adjusted the tones as needed using Hage Choro, Real Touch Markers, Mr. Weathering Color, etc.
I used Federation MS Gray for the joints. The markings on each part were basically leftover stickers and Gundam decals from previous kits.

EG RX-78 Gundam Real Type Color | ヘイカユウジ's Gunpla works