I paid $500 for my ae71, all the ae86's i found in similar condition were $2000+, so they are pretty good value, the only thing to remember is that if you want to run ae86 suspension you will need to change the brakes and steering arms for ae86 items, and you will need the front half of the ae86 tailshaft to mate up to the rear half of a t18 shaft should you want run a t series diff.
ae86 seats are not a direct bolt in either. They bolt into ke70's though, which is strange, but there you go.
Apart from that they look hot slammed on dished rims, but if you've got anymore questions pm me or add me to msn.