Build a prototype and some concept art, renders and schematics for a 4-robot digital sim video game (Unity3d, maya, google sketchup)

I need a partially playable prototype in unity 3d, 3d renders of characters and robots, concept art and schematics based on some 3d concept art and my design document. Botlink2 is a game in four parts. There are four simulated robots - each one is like a mini-game within the structure of the overall scenario. The four robots act similarly to each other but they are each designed differently. I can send a partial design document as the brief for this project, I am also getting some 3d concept art made. I will be ready to begin in April 2018. Perfectly fine to register your interest now, so long as you understand that the project is still quite a bit in the future. my budget will be around NZ$500. I am not looking for a finished game, just a prototype that allows me to express how the concept works and show feasibility of the design. The other pieces are to help show different aspects of the design - re: concept art, schematics, 3d renders. The goal of this project is to create a showcase that I can use to raise money to produce a finished game as a digital simulation of a robotic interactive scenario (which may in the future be an actual physical build - if it proves feasible.)