The plugin doesn't allow you to add comments to ads, nor does it allow you to add comments to blogs. Please give me some hints on how to implement this; it's very important to do so. I'll share my experience; just give me some pointers on where to start.

Such feature is not in plugin at this moment, you can request it as paid service at https://osclasspoint.com/contact
Hint: for custom integration, follow existing method (some simple update) and try to duplicate it.

That's already a good tip =)
I'll prepare all the changes and send them to you for implementation in the plugin. It's great that we can solve problems together.