Prices generally on forums and 'the bay' dropped significantly around Thanksgiving time last year, things had to be a steal to gain interest. I sold a lens I was expecting close to $450-$500 for $275... however I used it to my advantage and bought two lenses very cheaply.
FWIW I sold a pristine 4800 a couple of weeks ago, with network card, without RIP but with some custom profiles for $800 and I included some spare ink, at the same time I bought a pristine, low mileage 7800, with spare ink for $900...!!
Another example is the Mamiya AFD III/ Phase One AF, these are listed at B&H for $3,990 new and some Phase One dealers are selling them in EX+ condition, boxed with a 6 month warranty for under $1,000.
With the exception of say a 5D MKII, a Leica M9 and some Profoto bits... which are always in high demand, prices on the 2nd hand circuit have dropped.
One other thing... here in NYC where office/studio/desk space is at a premium and there are many many photographers, the 3800/3880 is the one they buy, despite the smaller ink carts the printer is small compared to a 4800. On that vein a 9800 is a beast and only really for specialized people (though we all want one)..
I hope this helps,
Keep advertising, use eBay and throw in some ink...!