Mike Rapoport wrote:

Paint generally counts only when done IMMEDIATELY before the sale.


How much of the upgraded avionics value was "consumed" during your
ownership? Normally one would depreciate the avionics and have a basis for
them, but is is fair to add the entire avionics cost to the airplane's basis
if the avionics were added 15yrs and 2000hrs ago?

You don't depreciate stuff in personal ownership. You can add the
capitol improvement of purchasing / installing avionics to the plane
(as opposed to maintaining what was there). You need to subtract
from the basis any residual value from anything your removed (if you
for example sell off your old stuff after it is removed).

If, the day before I sell the airplane, I replace the autopilot servos that
were 15yrs old when I bought the airplane and 20yrs old now, does that add
to the basis?

Probably those would be considered maintenance

If, when the airplane was purchased, all the bushings in the landing gear
pivots were worn out and replaced at the buyers expense, shouldn't that be
factored into the basis? I

Nope, correcting wear and tear is NOT generally counted. However,
certain fixes you have to right before the sale to make things
sellable can be added to your basis.


If you purchased the airplane with a crappy interior and it is like new now
then clearly you should add some of that cost to the basis but how much?

The "value of things" doesn't MATTER. The issue is WHAT YOU PAID FOR
and whether that is a capital (or other allowable) expense. You
subtract that from WHAT YOU SELL the plane for. The difference is your
capital gain.


If you bought the airplane with a run out engine and overhauled the engine
for $10K and TBO is 2000hrs and you have put 1000hrs on the engine, what
should you do to the airplanes basis? If you just pro-rate you get $5K
What if you had to do a top overhaul for $5K at 900hrs?

The basis is what you paid. How much time is on the engine is
IMMATERIAL. The change in value of the engine is taken care of in
your purchase /selling price.