Lots of clients hire me to work for them purely as a consultant.
Here is how that works:
My hourly rate is posted on my profile page.
The client hires me using an hourly contract.
Then I spend time consulting with the client. That can include setting up meetings to talk, or writing reports based on materials they send me.
The amount of time is multiplied by my hourly rate, and that is what they client is billed.