Print-Ready AI Image Enhancement

I have a single AI-generated picture in JPEG format that needs to be refined for professional printing at 18" × 27" and 300 PPI. I am also including a 2nd image (titled "freelancer image") to show some color changes / style edits that are welcome... (Budget: $250 - $750 USD, Jobs: Adobe Photoshop, AI Image Editing, AI Image Generation, Graphic Design, Illustrator, Image Processing, Image Upscaling, Photo Editing, Photoshop, Print Design)