Toggleable ground plane for midair condo building

Currently, midair condo builds are kind of a pain, since the only way to do so is to put a large object on the ground, move it up with gizmos, and then build on top of the base object.

To fix this, it would be nice if we could have some sort of adjustable building grid to help with placement, like 3ds Max’s grid objects:
image

For example, there could be options to have it follow the player at their feet (and have it snap to a grid so it only moves up/down at a certain grid interval), or to just stay in a fixed world position that can be transformed as needed.