This is actually possible in a roundabout way.
But I would suggest to put items inside a house with a locked door and no balcony or any other open entrances.
As for how to place items in a building..
What you need:
"Not having build the house yet"
"Items ready before building the house"
"best done with 2 people"
Step 1.
Your friend or you will have to use the preview mode for where to place the house, and then get it in the right position and area.
And from there this person will be the guide.
Step 2.
The other person will then take the items and place them inside the preview house that the friend can see, and he should guide you around as to where and how high you should place the object.
Step 3.
Once all items are placed in the locations you desire, feel free to build the house.
The objects will not trigger a blocked area error.
Thus your items will be inside the house when its build.
Note..
This can be done alone.. just takes a lot more time.
You "CAN" place items on the second floor of a building.. but this requires tons of workaround with stacking items till its in the right height. so not recommended.
Nice results with the 2 smallest locked houses.
Images.
http://prntscr.com/4w4lcr - Here is a workbench inside a house.
This was a test to see if it worked.. so I dint plan ahead and raised it to the floors level.
But taking it out now would just ruin it.. so left it there.
http://prntscr.com/4w4mdz - Planed Farmer house.
Items places in the correct height and areas.
Had friend guiding me with the preview of the house on his screen.
http://prntscr.com/4w4mwp - kept drying frames down on the ground to minimize the use of space inside the house.
they will clip up through the floor and you can still use them.
http://prntscr.com/4w8gfo - and done.
Hope that helps.
**Do not move objects once the house is build, you cant place them inside again**