Here you will find some interesting and possibly funny things in the World of Skyrim, such as being killed by a Dragon that farts fire. Glitches / Bugs are
in the system, But!! It's not to say that they are all Bad, they can make you laugh and possibly even Help you through the game in some way.
1. You can get any house as well as its upgrades for Free !! How you may ask, well it's as simple as this. Note: (You need 5000 gold to do this, but you won't use it) When you say "I would like to purchase the house" Hit the back button and store all your gold in a near by closet, drawer, barrel ext. He will give you your key, then just take your gold back. Repeat with the upgrades as well.
2. You can use a Wooden Plate, Platter ( The easiest ), Steel Plate, to actually push through some walls, this is also used in retrieving hidden chests in the "Underworld"
3. As stated "Underworld" in Num: 2, merchants have chests that they store all there items in, But!!! The player is not supposed to be able to access them. The game is written in a way that, if you enter a major city, cave, dungeon etc The rest of Skyrim is not loaded except the place you in, so if you somehow get out into Skyrim itself without exiting through a door, you enter the "underworld". Nothing else is loaded so you sort of free. Here you'll find these secret chests if you know where to find them of course.