How do users add a service?
In Feedback Centre 1 your users are able to add a service through the website then leave a review straight after. This is still the case in Feedback Centre 2, but it works a little bit differently.
The search on the homepage lists ALL the available Services, if one isn't found a prompt appears to ask the user if they would like to add a service themselves:

Once they click this link, they'll be taken to this page:

Once they fill out all the details they'll be able to leave feedback against the service. However please remember that the service will need to be published before reviews can be moderated.