Single seller service theme

Not sure if this is the correct place to write, but I am looking for a theme where i can sell my services.
I wanted something similar to a page like fiverr. But without the freelance part.

The main part of the site is about the chat functionality. Like there is on fiverr. Where the customer can register and chat with me, before they choose to buy the service.

Hope someone can help me

Thanks :wink: