It's pretty good.
One issue I have with it is scrolling only ever does 1 pixel at a time, so you have to click drag the upgrades to move them in a good way.
Just messing around with the demo, I haven't discovered how to place down the chest or the wardrobe that I purchased.
However I learned that it's possible to push the player around with the preview of the furniture, resulting in some pretty amazing speeds.
I can also be used to push npc's around. Pretty fun to mess around, but I smell some game breaking stuff in case this stays.