Create an app with flutter for selling new and used equipment

I am looking for someone to create an app on flutter for the sole purpose of selling new and used gym equipment. It will require the following features

-you can post your own images and list up your equipment
-you can chat with other users about specific products
-you can filter your search to find what is nearest to you and list specific
-you can use a payment gateway to purchase items through the app

The app does not need to be published, it is for my personal use as of right now.

I have attached some images of the general look and layout I would like to use. It does not have to be exactly the same but something similar would be great.

I would like the product delivered within 14 days at most but around 10 days would be ideal.