I usually add up the sum of the parts, and if they total more than the asking price I go for it.
Here you've got:
Truss fork $25+
Frame $25+
Skip tooth components $25+
Wheel set $25+
Bars $20+
And I'm being conservative because I don't know condition. The rest is icing on the cake. Stem, seat, tires if they're good, fenders. If parted out you could easily double your money or more, so you can't really go wrong.