Instructions
Purchase as many pieces of luxury furniture as you can from a furniture shop, such as the one in Bowerstone or Bloodstone.
Go to your house and examine the deed on the outside of the house with the "A" button. Select "Redecorate" from the list and enter the house. If you do not currently own a house, follow the same steps but instead choose to purchase the house from the deed list. Purchasing a house with a low cost will be easiest to sell for double.
Replace the old furniture in your house by going up to it and pressing the "A" button. After replacing all of the furniture with luxury furniture, exit the house. The luxury furniture will increase the property value of your house.
Spend money in the town where your house is located to drive the economy up. Do not steal from any of the shops or it will hurt the economy. Spending money in the town will increase the property value of your house. Continue spending until the property value is double the price you paid for it.