Goldpiece value of this Intelligent +3 Chaotic Thundering Greatsword?

[Corwin the Confused]

What is the goldpiece value of this intelligent +3 Chaotic Thundering Greatsword?

DemonClaw

+3
Chaotic
Thundering
Special purpose to kill lawful outsiders
+6 against lawful outsiders (each successful hit causes the lawful outsider to permanently lose 1 point of AC)
Ego 25
Speaks telepathically with wielder
Grants wielder Improved Initiative feat
Grants wielder True Seeing

 

[Astlin]

Hmm, looks like an epic Monk killer.

 

[Vyvyan Basterd]

A message from Corwin's DM:

I read the book.

I have the value. In the DMG you can see its value in the Intelligent Items section. You missed some abilities of the sword. It has three 'primary' abilities and one 'extraordinary' ability and the chart in that section lists a market value. Add that value to the market value of a +7 greatsword (+3, +2 for Chaotic, +2 for Thundering) and you've got your price.

The +6 is part of the sword's special purpose abilities which add nothing to its value because, as you well know, the special pupose gives some nice powers, but it is equally a hindrance to its wielder.

I believe the total value of the sword would be 153,350 gp.