I think the starting point for a four string Distillate in good condition would be around $1,900. The fact that it's a six string, and for me the fact that it appears to have the Classic taper, increases the value. The Knobby headstock and Scorpion body are nice upgrades, and I think they add to the value as well. The front and back Quilts appear to be 5A in the pictures and also add to the value. There may be a tinted finish, but that may just be the lighting. There seems to be something on the 23rd fret in both front pictures; could be reflections, but it's in both pictures; worth asking about.
No case! Add the cost of a case to your expected outlay. Also, I would be very concerned about shipping a bass without a case, especially a bass with Omega tips.
I see he has answered a question that the width at the 24th fret is 3, that would make it narrower than Classic taper; or could be a less than accurate measurement, since Classic taper would be 3.125 at the 24th, I'm guessing it's Classic.
Personally, the style of the listing's text tends to suggest that this is not the seller's personal bass. However, looking at the feedback, he has sold other basses and amps, and a fellow club member has made a purchase from him.
Really nice six strings are rare; and this looks really nice.