values are dependent on what you are using them for. Are you looking at putting a price on a home to sell in which case you are determining the value of the comparative homes that have sold in the neighborhood (see a reputable realtor who will tell you like it is, not give you ridiculous answers and put a higher price in order to get your business), intending to put an offer on a home (see a reputable realtor who will do a market analysis and help you to determine a fair market value for the home), planning on refinancing (the bank will only accept their own appraiser's value), planning on fighting your tax assessment (talk to a reputable realtor who is experienced in helping people with their taxes (the counties have advocates who will help you, and there are some of us who are experienced in doing it), your insurance agent will put a value on it based on what it will cost to rebuild if it is destroyed.
In general, the value is determined by what someone is willing to pay for it now when most of us talk about value on Trulia
Let me know if I can help you further
If you want to find the value of a home, you really must meet with a real estate agent. An agent who review with you the comps for the home plus review the many different variables that will affect those comps. Determining the value of a home is simply a math exercise. Consideration has to be given to such factors as: condition of home, location, schools, shopping areas, staging of home, market conditions, taste level, taste level, taste level.
These days I am suggesting that the potential seller have an appraisal of the home before listing it. That sets the stage for both the seller as well as the agent to come to reality. Also, these days what you paid for the home has nothing to do with the current value of the home.