The quality of your photos makes the difference. For a nearly professional result, even if you are using your smart phone, follow these tips.
1) Clean the object as well as possible
2) Place the object in a place with natural light or otherwise well lit
3) Use a white background (a white sheet can help you!)
4) Place the machine/phone on a stationary plane or place the arm on a flat surface
5) Capture the entire object
6) Photograph from different perspectives (at least front, back, side)
7) Photograph any defects
8) Do not add any distinguishing marks
9) Do not use filters or special effects
10) Take original photos do not download them from the internet
11) Photograph the object in its functionality and size (e.g. vase with tulips inside)
12) Show details (e.g. take a specific photo of the fabric or handles)
13) Photograph labels, tags or signatures attesting to the provenance of the object, if any
14) If you are selling a group of items, take also a picture of the full set
15) Upload at least 3 photos.