G Constructions logo

My name is John and I am looking to have a logo designed for my construction business, 'G Constructions'. The logo must have a modern design and should include dark colours such as black and white, red and blue, or green and yellow. It is essential that the logo must be vector based so that it can be used on multiple media channels and scaled to different sizes without compromising quality. Please submit your proposals along with a portfolio of your past work and a timeline of how long it will take you to complete.