3 simple steps.
Users contact me , i provide a demo , if they like it i provide them a production account , they work for 1 month , if they are happy with the results they pay.
easy as 1-2-3
Then ask any of these users with a good rank here on the forum to simply write one short post in this topic about how everything worked out great for them with the implementation of your proposal.
And this is exactly what will really help you promote your proposal on the forum.