This has morphed into a bizarre situation.
First let me say that I very much appreciate all of the answers you provided. While I did not get the answer I wanted, everyone certainly gave answers with well reasoned arguments.
After an extensive search yesterday my sister and I came across the complete appraisal documents from the last re-fi that was done just after her husband unexpectedly passed away. I wish I had been living in this area (Nashville, Tennessee) at that time so I could have helped her with financial and other issues. But unfortunately I was not.
Anyway, that appraiser made a major mistake. He calculated around 300 extra square feet in the "main" section of house by adding 14 feet to the width of the house. I.e. it is actually 60 feet wide as the current appraiser shows, but the previous appraiser had the width as 74 feet. Another strange thing is that the local tax authority also added extra footage to the width. But they only added an extra 10 feet and therefore show a width of 70 feet. Two different people making the same mistake? It is just a coincidence that the extra width adds up to almost the same footage as adding in the workshop area. That is why I thought that this area had previously been included in the living space.
So my sister finds herself to have been paying taxes on 1708 square feet for years instead of 1451. And the value of her property has been calculated using this extra footage for at least 10 years, (that I can document) and maybe even longer.
Now, just when she has need for the property to be recognized at the "expected" value, the appraisal comes in 30k below tax value, close to 30k below the last re-fi, and about 45-65k below what 1700 square foot comps are showing.
I have been racking my brain on how to resolve this issue and help her out. I have come up with a couple of possible solutions and I would very much appreciate some advice from the experts on this forum before proceeding.
What I am really looking for here is the possible effects on a re-appraisal.
Both of the following solutions require
1. cutting a new door into the existing workshop wall facing the main house so that access can be made without going outside
2. dry-walling the inside of the existing room
3. reinstalling the carpet I removed
4. reinstalling a window unit for heat/air (very popular in this area)
As shown in the diagram and images from the first post, there is a carport/parking area between the house and the workshop, which is the main reason the workshop area isn't included in the living space if I understand correctly. Here are a couple of close-up photos made with my phone yesterday that may help envision what I am suggesting.
Standing on the deck looking right:
http://img687.imageshack.us/img687/9571/image135o.jpg
Then left:
http://img716.imageshack.us/img716/3884/image1362.jpg
The first solution is to enclose the carport area with screened walls to make a screened in breezeway. Obviously the fastest and cheapest solution.
The second solution is to enclose the area making another complete room. I have a good friend who is a trim carpenter and framer and I can do the painting and carpet work myself. Only two walls would be necessary and we should be able to have that completely finished in a week or less. In fact, the house next door has the same floor plan and has had this very thing done except that they expanded the area into a single room as opposed to two as I am suggesting.
Please let me know what you think of these two solutions to our problem and how they “could” affect another appraisal.
Thanks again for your advice...George