Animated Video for Healthcare-Related Solution

I have a script for a web-based healthcare service startup. Script is 2-3 minutes. I have a basic concept of what I am looking for but need to work with an experienced vendor with a strong portfolio. The video will be used primarily for potential investors and partners. Needs to be catchy and clear. If the project is successful, there will be immediate follow-on projects as I need 3-4 different videos that tell different parts of the story. This is the first "introduction" video. I am going to want to see proof of capability before we start and I will want a relatively early-stage milestone to ensure we are on-track - and if not, I will pay that milestone and end the project and find a different vendor to work with.