Hi there,
Is your technology something like Tesla?
I can make an introductory video that can be used as an advertisement.
We can render it realisticly, but I don't recommend it since we are focusing on a driving platform.
I will render your animation using Eevee and it may take longer than 20 days based on the time of your video.
I have 8 years of experience in 3d modeling, texturing, rendering, and animation.
So rest assured that I have done many projects similar to yours, and your project will be in good hands.
Hope to hear from you soon.