I am very detail oriented and will replicate your flag's design to the smallest detail. It is difficult to estimate how much to charge for this job without seeing your flag's design, so I have bid on the high side. If it is made of a few common geometric shapes, that could take less time than if it is made of organic shapes, such as a crest or medallion. For the first milestone, I would use heavy body acrylic paints on canvas to make a 1/4 scale rendering of your flag, scan it, and send the digital picture for your approval. If there are many fine details in the design, they would be lost in a 1/4 scaled rendering, but I would paint color swatches, scan them, and send that pdf for your approval. For the finished project, I would paint the full size version you desire with the same paints on canvas and scan the flag to send it as a digital file. I would like to discuss the details of this project with you in order to meet your requirements (dimensions of flag, type of digital file, and resolution) and fine tune my bid if needed.