Quoted from PanzerFreak:Well not all games are treated the same. Condition is king and a STTNG with say new ramps, subway and a nice or new playfield will command a much higher price.
I'm doing a playfield swap on my STTNG right now. New ramps, new subway, all LED's, ColorDMD and more. When its done I would never let it go for less than $5,000, probably no less than $5500, maybe more.
I am in the process of the doing the same. I think STTNG is a great pin. Better than the Stern ST. Add a pinsound card, color DMD, and some cool mods and its incredibly fun! I plan really customize my STTNG like my MB and T2.