Good question. If you mean the tax appraised value in my opinion this has nothing to do with the market value. Yes in theory it should, but there are so many other factors to take into account. It goes both ways. Sometimes homes aren't worth anything near the tax appraised value. Sometimes they're worth way more than the tax appraised value. There are a myrid of reasons for this. One thing to remember is that the tax appraisals are done usually by a method called mass appraisal. The appraiser has likely never seen the house, never been in the neighborhood, and most likely working off data only. I often wonder if they also don't back into the number. We can see next year....I often wonder if "our budget is X, there for we need Y tax revenue, and that is 10% below what we had last year, so let's raise all the values this year by 10% to meet budget. I've seen the tax appraisal swing from year to year as well. One year $20000 over on a $150,000 house and the next $20,000 under. All this just goes to show you that these are not reliable numbers to use for anything.
Get a realtor to help advise you. We can help you determine the appropriate values and offer to make. One idea is that we normally do not suggest you buy a $500,000 house in a $250,000 neighborhood. Financially it's normally better to be the other way around, buying a $250,000 house in a $500,000 neighborhood if there are such variances. Most builders or banks can't take off 30-40% a house listed at $250,000. There may be an occasional deal like that...but few and far between. I would also advise caution of buying a house that has been vacant for 3 years. You definately want a thorough home inspection on these with all utilities on. Seals dry out, varmits get in, things freeze up....
If you're looking in North Ft. Worth I can help you, if you are looking in other parts let me get a friend to help if you don't already have a realtor in mind.