We cannot set a base price for every item of this game, they change too much for various reasons.
Slicers of Vengeance were worth 50+ dts two years ago and now they go for about 20 pds each because they became easier to hunt during Valentine Event
PGF was about 50 dts many years ago because it used to be in the donation list and now people ask for 350+ dts as everybody wants one.
If I, as a GM, decide today to "set the price" of Varista to 99 pds, would people really buy Varista for 99 pds?
The community totally decides the prices of items.
Thus it is always better to ask for price checks if you are not sure about what an item is worth, because you will get current opinions and not something that may be obsolete.
@O9B066 posted the link to a Price guide made by a GM, yet there are many item prices in it that are much different from what they are being sold at the moment.
Not only it is a hassle to keep such a list up to date after each event, but also that doesn't take into consideration the variable stats of each weapon (20 hit? 50 hit 70% native? 80 hit?...).
If you ask me a PC with the detailed stats, I am able to give you an answer as accurate as possible (regarding the demand and the average price of the moment). I can't do that in a Price List.