Adding realism to digital render

I have a four views of a digital render placed in a real world photographed scene. It is a 3 metre high glossy glassfibre (plastic) sculpture placed in a field. The images look good, I am happy with how the views describe the design but it is easy to tell that they are computer generated. I would like someone to use AI tools to increase the realism. Ideally it should be unclear whether this is a photograph or computer generated. I would be willing to sacrifice some of the quality if that could make the scene more convincing – less dramatic, more dirty realism.
My proposal is for you to spend one to two hours on one of the images as a fixed price starter, if this works out we can commission work on the remaining views and/or further work all four
If you could give an indication of what needs to be addressed to achieve better realism and the tools/strategy that would be used – this will help guide my selection