It looks to me like the jeeps converters are wire type converters which are mostly sold buy them pound.They bring around $45-50 each on the big ones and the little ones i think around 30-35.
The ford explorer should have been a low grade honeycomb which s about $50-55
Taurus pre cat 35 is about right the reg taurus honeycomb is 55-60
the altima is a small foreign it is worth 95-103
so my total is $378 is a average of what you should have gotten.
Also you said something about wheels what are they paying for them.I think i get $0.84 per lbs which is anywhere from $16-$18 per wheel on average