How to compare/valuation of features

Hey, Folks:

Grab a beer on me, I'd like to solicit some more opinions. If you've read
the other thread on airplane comparisons, you know I'm shopping for an
airplane.

So, I have another question. This time, not how to compare airplanes, but
how to make an apples-to-apples comparison (money-wise) between different
specimens of the same model for sale. I've used AOPA's Vref, but it's
unsatisfying in this regard for several reasons (among them, it doesn't
really answer my questions below, and it's cumbersome to input different
parameters to try to do so anyway; plus, there seems to be general agreement
that it overvalues by around 10%?). The rest of my studies have similarly
failed to completely address my questions below. Obviously, each of these
will vary a little based on airplane and exact choices made, but I'm looking
for a ballpark.

- Engine time. Seems simple enough--divide the time on the motor by TBO
and multiply by overhaul cost ($25K, I seem to be hearing? [oops! I'm
trying to join this club, better get used to the jargon: make that 25AMU
]). Throw in some English based on the average annual usage (more is
better), and you can compare two different time engines. Fair enough?

- Avionics--the big one. Conventional wisdom seems to be to get the
airplane with all the avionics in it you want, because you'll never get the
same value out of buying new. OK, I'll buy that--but, at some point, the
lines have to cross. To illustrate with an extreme example, assume I find
an otherwise satisfactory airplane that has totally dated avionics. What's
a soup-to-nuts panel cost, brand new, installed? Is 50AMU in the ballpark?
Not chump change (hardly!!), of course--but, it *is* sometimes within the
spread of the price ranges I see in a given model, where the primary
difference appears to be the panel....

- Paint. What's a quality paint job cost? 5AMU?

- Interior. What's a new interior cost? 5AMU?

- Any other big valuation points I should be looking at with a similar eye?

Thanks!
--
Doug
"Where am I to go/Now that I've gone too far?" -- Golden Earring, "Twilight
Zone"
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