lets see:
keg - anywhere from 30 to 100 on craigslist - more from a legal distributor - lets call it 70
Angle grinder and cutoff wheels: cheap for under 30
decent hole saw or step bit - another 10-20( if you already have a drill)
2x heating elements - 35(camco 5500w are 21 each)
cords and plugs - $40
Welded couplings - cheapest I have seen is 25 per weld - there two I would have done here so - $50
valve kit: 25
I personally don't like the double element thing, but those are easy to get a seal for if you don't want one.
so, if the welds are good, the build isn't crap - that price isn't aweful. the pot seems like a weird configuration but you would spend a bunch more getting a megpot or blichman the same size.