Looking for Feedback to Improve and Promote My 3D Model – Your Tips Are Welcome!

The print cannot reach the top of the can. There should be a joint ring (a few mm) it is not painted.
And why not add a screenshot with the model wireframe?

Here is my advice , and clearly you are a beginner in this so dont take anything personal :)

1. Choosing the model - You are trying to sell a Can (which is the most basic model to make and freely available on the internet) for 30$? and its the same can with different textures which arent even scaled properly , with bad HDRI lighting of an environment that doesnt makes sense , and same matte shader which isnt even correct for how a can looks like (Images in the end are better than the ones in beginning)
2. No description or text on any of the images which makes it hard to understand the model
3. No Wireframe view to show the polygons or topology
4. Model is of a Can and your description says Cola bottle

Before modeling anything - find a reason why people would want it and find tons of real references of how it looks

Delete this model and restart and this has nothing to do with your model but the username is hard to remember so maybe try to rename it something easily memorable
Good luck.