Illustrator: How to un-merge non-contiguous objects previously "united"?

Question

I created dozens and dozens of odd shapes in Adobe Illustrator by drawing lots of overlapping rectangles. Then I did Select All, and used Pathfinder->Unite to turn them into polygons. Now I have a bunch of polygons, true, but as a side-effect, they were combined into one single object.

Is there a way to either

1. Unite all my original rectangles, but keeping non-contiguous shapes as separate objects?
2. Automatically separate the resulting single non-contiguous object into a bunch individual (contiguous) objects?

I know about the Shape Builder Tool. I know that I could use it to painstakingly build individual merged shapes, one by one, instead of using Select All, and then using Pathfinder->Unite. I know I could enter polygons in the first place, but I need the rectangle representation, and it is faster and more reliable to draw rectangles. (I am sort-of "rotoscoping" a high-tech "Manhattan geometry" design).

The problem is that there a hundred-or-so of these shapes, they are irregular and close to each other, thus hard to select. It would be very time-consuming (and error-prone) to apply Pathfinder or Shape Builder to every single group of overlapping rectangles. And my next design is even bigger.

Answer 1

If you Select All and do Pathfinder> Unite with non-contiguous sets of rectangles it creates a Group. When selected with the Black Arrow the entire Group will highlight.

You can either open the Group in the Layers Panel (click the arrow to the left of the group) and then individually select each non contiguous United object and manipulate them separately. Also you can Ungroup them (Object> Ungroup) and select them individually either on the drawing or in the Layers Panel.