This is a follow-up to a previous post in which I hinted at an "option to submit premium listings" to a custom store directory: https://premium.wpmudev.org/forums/topic/diy-create-a-categorized-directory-of-marketplace-stores-with-unique-store-ratings-review-pages
The "premium listings" are in the form of paid user-submitted posts to blog categories of your choosing, and they can even be used for a custom Advertise-on-This-Site scenario. At the heart of this technique is WPMUdev's unique Pay-per-View plugin:
Thanks to help from @Hakan in another thread to pin down the most secure way to delete the cookie left by the PPV plugin, Pay-Per-Post is now a workable thing. Here's the thread for those interested: https://premium.wpmudev.org/forums/topic/ppv-with-gravity-form-post-form
Once I finish working on the write-up to detail how to git 'er done, I'll post it in this thread. Stay tuned... it's ossum!
In the meantime, you can see the technique working here: http://etcemall.com/
Click any ad placeholder - "Feature your store here" at the top of the page or "Click to get your ad here" in the footer. Then go ahead and click the pretty blue button with the $ sign... don't worry, we're in sandbox-mode at PayPal so it won't cost anything to try it out.
Back soon with more fun...