We have found that appraisals are typically less than what realtors assess.
What they say the market goes for is not the same as what house is 'worth'.
Just went through this with a house we sold for a relative.
What people will spend to get into a neighborhood (what realors depend on) is not the same as what bank is concerned about - if they have to sell the house in a hurry. They usually go buy what it last was purchased for and what additions/money was put into it - kind of thing.
That's my understanding of it. So it's usually less - especially if houses have been in demand in your area and prices are a little over-inflated.
ETA:
Who ordered the appraisal?
Our house appraisal is way lower than what a realtor would value our house at - this is really typical. I find this confusing, and just read it to my husband.
What other homes sell for fluctuates all the time.
Banks want to know what they can unload your home for in case you can't make your payments. So of course whatever houses are assessed at will be very conservative.
Can you provide more details?
If you go on any realty sites, you'll note that houses on cul-de-sacs, etc. are generally priced higher than ones that aren't, etc. Half baths are not worth that much more. There are so many factors that go into these assessments. Floor plans, layouts, etc.
If it were me, I'd ask the banker how much of a difference this means for you once these errors are cleared up. If you want a second opinion, get one. What else can you do?
Good luck :)