Yesterday I could drag an item from my content browser and the item would snap to wall of the house I am working on and then could just rotate to make it right. Today when I try to place an Item it will go through the same wall and to the ground outside the house to where ever the cursor meets. I have no Idea what I did to affect this. I have already tried changing to different snapping options on and off. Which still have not changed everything snapping to ground now. Even with surface snapping off
The collision on the wall is turned off 
Tired that. lol
Actually not sure how it works in tandem but fixed this issue by ticking “Allow Translucent Selection” under settings. Not even sure when I un-ticked it. But now all works perfect again.