Assuming you bought a house 10 years ago and what to have some idea what it is worth you would need to:
1. Look for similar houses in your area that have sold within the past 4 months (usually I would say six months;
2. Contact an agent and ask them to do a comparative market analysis on your house; or
3. Commission an appraisal of your house.
There are numbers you can crunch and trends you can overlay and ratios to apply, but these are all exercises of self-deception.
Analyze what the current real estate market is doing regarding like kind homes. adjust for tangible asset discrepancies and the result will be a value in which you can have confidence. Most real estate professionals can do this for you. We do it many, many, many times a year.
Or go to Zillow. That's EZ, but as you know, they are the masters in pubic deception.
Best of success to you,
Annette Lawrence, Broker/Associate
Reamax Realtec Group, Palm Harbor, FL