Add default or option image to post form

[Morgain]

I'm interested in either advice to get started on the default image display, or a paid addon to do it all.

What I want has 3 bits.

1. THREAD STARTER DISPLAY
I want to assign a default image per category or per forum.
This image displays in the thread starter post as default, float right.

The preview text that shows on a search would show left and this image on the right.
Under these two top blocks next to each other, the rest of the text shows as normal, if any.

2, REPLACE DEFAULT IMAGE OPTION
the thread starter wants their own image they can upload it to replace the default (like replacing an avatar and about the same size as the large size avatar).

3. LATEST!
A search results page showing Latest posts with the top part of the new design displaying for each Latest post.
Any new post on a thread appearing on this Latest page (not only the thread starter) displays as the new design with the image shown in the thread starter.

ROW 1: postbit - preview text - image
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ROW 2: postbit - preview text - image
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ROW 3: postbit - preview text - image
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