In whiterun when you're given the option to buy the house for 5,000 gold there is a way to get the home and keep all that gold. This proves to be especially useful for lower level players who want a house, but don't want to blow all their cash. So, make sure you talk to the Jarl's attendant who sells it to you when he is near a chest, dresser, or something you can store you gold in. Go through the dialoge, say you wish to purchase it, then once you've pressed A to purchse, quickly press B a couple times to leave this screen and then quickly deposit your money into the chest. This also works for all the upgrades available to the house. He will indicate they'll be in your home next time you arrive, and you'll see the key placed in your inventory but you will keep all the gold.