This is excellent I've only been selling on this app for almost two years and have 5 stars with close to 300 ratings. I believe it is very important to have good ratings, clean and clear photos and descriptive information on the product. Since I do sell professionally my photos are always clear but even when I first started I still believed that having good pictures will get people's attention and get items sold. I take pictures with my iphone 7 by the way and edit them using an app so you dont need a good camera just good lighting.
I had a friend who was selling his watch for $20 and I told him it could be sold for more if he had clearer and more "attractive" pictures so I took photos of the watch and sold it for $40 and the retail for it was $90 so I got him almost half his money back for a used but clean watch.
Also communication is important this goes for everyone not just professional sellers, being kind and respectful is important especially since you're dealing with strangers, people you've never met, and if you're selling an item and someone is inquiring about it there's no point in being rude or if they're asking too many questions and you get annoyed being patient is key.
One thing I notice a lot is some people sending very blatant messages please people be more clear and write full sentences we are not texting our friends here no acronyms or one word answers.
All in all when speaking to a buyer or seller through messaging be clear and be kind and don't message people on here just to harass them on something they are selling unless its something illegal or dangerous just report them no point in arguing with them going back and forth.
Being a great 5 star seller/buyer by selling great products at a good deal, communicating and being trust worthy sometimes isn't enough.... People tend to forget the obvious Once you meet up with your buyer/seller make sure to ask for a 5 star rating and tell them you will do the same. This clarifies and prompts the person to do so as well as seals the deal that you and that person had a great transaction and your both happy. Politeness and sincerity go a long way! Remember : Ask and you shall recieve - simple
Also another tip if someone is apprehensive about buying from you for any reason, assure them your rating is great (if it is) and that you intend on keeping it that way. It shows that you care about being a long term, trustworthy buyer. Also make sure you become a an approved/certified seller. I don't do business with someone with no rating, no posts, sales, picture or cert.