Not really a solution, more of a work-around for your specific example:

I wanted to do the exact same thing in one of my settlements. What I wound up doing was this:

1. Lay down a wooden floor as a base for your Merchant Stand house. Large enough to accommodate all the stands without too much crowding.

2. Erect metal walls around the edge of the floor (use the flat metal walls).

3. Replace one of the edge floor panels with wooden stairs (use the stairs that have a floor on the bottom and top that is the same size as the floor panels).

4. Attach floor panels to the top of the stairs, creating a second floor.

5. Attach metal walls around the edge of the second floor.

6. Place metal roof panels on top of the second floor walls.

7. Scrap the flooring on the second floor.

8. Replace the stairs from step 3, with a standard wooden floor panel.

9. Decorate and light to taste.

What you wind up with, is a floorless second floor hovering a few inches above a roofless first floor. If you are close enough it looks kind of odd and kind of nice at the same time. Use Science! as an explanation for the levitation.

Paisley for Defense?

Great ideas. Several of those I had thought of also. I hate how u can't stop or edit supply lines. How about a mini map n u select where u want to open up. Then they change color to indicate active supply line. Need to be able to customize companions outfits. At this point I give mine a good armor n they still wear original clothes. Settlers names should be changed to their job, farmer, guard, etc.

I like the idea of small box listing their job.

Wish settlements could be bigger n wish it didn't limit what wall floor whatever goes where.

I started building Sanctuary up to be big at first then realised no more than 10 plus my charisma is all i can have. 40 beds wasted. Of u have one bed one food n one water per settler I should be able to have that many people there. Also u should be able to scrap everything inside the zone not just certain buildings. Why spend wood n steel building new wall when should be able to repair walls on existing houses.

Walls should have hit points. What's the point of building up a secure village of npc walk's right n starts attacking. If u spend an hour RT building n designing it should mean something.

You can do that now.

Just giving them something doesn't do anything. You also have to tell them to use it.

As an example, Piper.

The first thing you have to understand is that the cloths a companion is wearing, does not show up in the trade window.

Additionally, most of the default outfits that companions wear do not allow for the use of layered armor.

So in a trade window, Pipers default outfit (Red Leather Trenchcoat) will not show up and even if it did, she would not be able to use the armor.

I am a PC player, so I will be using those keystrokes in my example. If you are a console user you will probably have different buttons to press.

The first thing you need to do is to get the companion out of their default outfit, and the only way do do that is to have them equip something else.

So you need to transfer an outfit to her that can use layered armor. I use a Harness (mostly for the eye candy effect).

Transfer the harness and then highlight it. The bottom of the window should show the commands you can use. On the PC they are:

E) Take R) Take All T) Equip X) Inspect TAB) Exit Z) Sort

Tap the T key, She will put on the Harness. Harness will disappear from the her inventory window and Red Leather Trenchcoat will appear.

Now that she is in the harness, she can wear the combat armor pieces over it. Highlight each in turn and tap the T key.

It is important to understand that ONLY the outfit she is wearing is hidden. Hat, armor, weapon, etc will always be shown. Of the visible items in her inventory the ones she has equipped will show a square icon to the left of the item. if it is not equipped that will be blank. Highlighting an equipped item will change the prompt from T) Equip to T) Unequip

If you should issue the Take All command ('R' on the PC) you will transfer all the gear they have in their inventory EXCEPT the hidden outfit they are waring to your inventory.