How long will it take to create these models?

Not sure if this is the right section or not, if it isn’t, let me know.

I want to hire a team of developers in the future for an FPS game, so i am wondering how long would it take for a single developer to create a cartoony scene and a realistic scene from scratch, excluding animations and the server sided work.
I need to get an idea, so the budget i need in mind would be more accurate.

Thanks!

Realistic scene example: https://i.imgur.com/5uJbdgp.jpg
Cartoony scene example: https://i.imgur.com/nNML7iy.jpg

How long would it take you to create a cartoony version of the realistic scene example?
How long would it take you to create the same scene as the realistic scene example?