Modded gear on the used market.

Friends, during my search for a used cd player with a volume control, I have come across several players whose owners have spent hundreds or even thousands on modifications. I am curious what the conventional wisdom is regarding the premium to be paid for such upgrades. I realize that a mod is not a mod is not a mod. But is there some market consensus that a unit "appropriately" modded by a reputable outfit is worh x % more than its original sibling?
It is worth less IMO.
It is worth less IMO.
I somewhat agree, but it depends on the reputation of the "Mod'er". In many cases sellers can and do command a healthy premiums. eg Steve McCormick's mods on the DNA amps.

If the mod was done by someone totally without credentials I would stay away, unless I got a really good (ie low) price.
I strongly disagree that a modded player is worth less than a stock player, especially if done by someone with excellent credentials: Modwright, Exemplar Audio, RAM, etc.

However, the used value of the mods is a fraction of their original cost. Assigning a percentage is of little value. I would recommend watching the listings for a model you are considering and noting the units that sell quickly, and their asking prices. These will have been priced correctly.

If a unit lingers in the listings, you can be certain it's priced to high.
I agree with Tvad. I also feel that a modded unit by a reputable modder adds value over a stock player. How much value depends on who did the mods. Some modifiers hold their re-sale prices better than others. Best to watch the market as Tvad suggests to get a handle on which modifiers are the most popular.

For some reason I've noticed that digital sources seem to be the hottest items for modifications, much more so than amps, preamps, etc.

My opinion-you will never get the cash back out of a mod that you put into it. With that said, if you are willing to make that sacrifice, it's well worth it.

Chris Johnson of PartsConnexion modded my Music Hall and I couldn't believe that it was even the same cd player when it came back. For under $400, he took it to an entirely new level that I would have had to spend thousands to match with a retail unit. He even sent me a ziploc of the crap he removed. About 4 oz of little pieces really do add up...
I have said that before:
Mod only the gear that you absolutly love to begin with.
I rather modify an already good design with cheap parts then poor design with premium parts.
You won't get your money make sure that's what you want to do.
There are only few guys that I would let to touch my gear.
Many srew-ups out will see those often up for sell.
Do not believe some statments like: It takes good couple hundrets or thousands of hours to fully break-in. That is a lie.
If it doesn't sound good after first 100h , it probably never will.
Good mods are worthy investment.
But it is not something that will performe some sort of magic.
It will on the other hand inprove on already good system.

Just my 2c.