Engineering 3D Models Creation

I'm looking for someone to create 3D models for an engineering project. These models will be used for presentation purposes, so they need to be visually appealing and accurate. I have shared my own efforts which are not up to standard!

Requirements:
- Create 3D models and export as JPG/.PNG
- Models should be suitable for presentation

Ideal skills and experience:
- Proficiency in 3D modelling software
- Strong attention to detail
- Background in engineering or technical fields is a plus

Please provide samples of similar work.