As I played through Skyrim after downloading Hearthfire, I realized something that would make a great addition to the game. The ability to create/buy and maintain your own store in a hold would be alot of fun, kind of like in the same way Hearthfire is. You could either transform one of your homes that you own in a city into a shop, build a shop, or buy a shop. Name the shop and furnish it. Hire a shopkeeper (possibly a follower or maybe have some new characters roaming the city seeking employment) In your shop you can fill the shops inventory with items you would like to sell, and over time the items will gradually dissapear and your shopkeeper will have the earnings for you when you speak with him (after he has taken out his pay of course). Maybe you could even tell your shopkeeper to buy certain items from customers, possibly by giving him a sample of what you would like him to purchase (a potion, soul gem, ingredient, etc.) or by simply giving him a category such as ingredients, potions, ingots/ores, etc. The shopkeeper could buy these things using a portion of the shop earnings. I had this idea when realizing that I was often becoming over encumbered with massive amounts of valuable things. I want to turn them into money, however never can find a shopkeeper who can buy it. This would be a great way to get rid of those valuable things that tend to weigh you down that you simply dont use. I also thought of a couple interesting random events that might occur through your shop. Occasionally your shopkeeper might tell you he bought a rare item off of a customer for a steal, and you can get it. Also, thieves can rob some items from your shop while you are away and your shopkeeper knows where their hideout is. This becomes a typical clear the hideout quest. In the final chest you could find your stolen items/money.

I dont know how this could fit into the game the most easily, wether a DLC, part of a larger DLC, or an update to the game (or to hearthfire). Hope you guys found the idea interesting, please leave feedback!

(if this idea has been posted before sorry )