Required Graphic Design,3D Design freelancer for Family Portrait Digital Painting job

I am wanting to have a large family portrait digital painting done for my Grandma's 80th birthday. There are a total of 38 people. We would have to compile multiple photos many of the people have never been in the same room together, and some have passed away. The painting doesn't need to be overly large, just big enough to distinguish who is who in the painting. What size do you think would be best, what would it cost, and when could we have it done by? Thank you so much.

Skills & Expertise Required

Graphic Design 3D Design