Modelling dynamic section (select objects in section)

I am wondering if there is a way to create a 2D cross section of a wall, where I can choose the depth of the cross section.I have found this tool - It has dynamic functions, however I don’t know if I can select the depth.
I have attached a couple of screenshots showing what I want the section to look like (manually drawn) and what I get using the section tool. Also if I want to have a section of a particular part of the wall and the the entire thing, do I have do split the wall into separate solids?

Hello - Making a plane, trimming as needed and then intersecting it with your walls seems like the most versatile if I understand what you’re after. Use History if needed and you can leave the planes on an off layer to get them out of the way.