A. The differences are enormous and to answer this question would take many pages. Briefly let us use this analogy. Aircraft price guides are published, marketed, and distributed by book publishing companies. The facts are, they do not appraise aircraft, they do not even gather or generate their own data. Rather, they simply send out a questionnaire every 3 months to subscribers of their books and ask a few questions which at best are very vague. From these questionnaires the book publishers generate their data base.

An interesting point to consider is this. Nowhere on these questionnaires do the price guide book publishers request information regarding:

2. The aircraft’s damage history.

3. Engine or airframe modifications, if any.

4. Make and model of installed avionics and if there were any avionic upgrades.

5. Physical condition of the airframe including surface corrosion etc.

6. Inspection status of the aircraft. For example, the aircraft may have been out of Annual for some period of time or/and there may be Airworthiness Directives and/or mandatory Service Bulletins which have not been complied with.

7. Props and time since overhaul.

8. Engine overhaul status. For example, was the engine field overhauled to FAA overhaul service limits or overhauled to factory new limits or a new engine.

9. Condition of de-ice equipment, instrumentation and other systems and components.

It is truly a mystery how one could generate an accurate database of aircraft values without a clue regarding the condition of the airframe, make and model of avionics, damage history, airframe or engine modifications and all of the other important value points listed above.

The National Aircraft Appraisers Association is the only organization in the world which considers all of these factors in its database. Additionally, all of the information the National Aircraft Appraisers Association uses is verified by its 350 Certified Aircraft Appraisers members who have physically evaluated the aircraft, and each Association member subscribes to the same evaluation criteria while performing the appraisal. The end result is an extremely accurate database that is verifiable.