NIL- If you or anyone buys a AE86 thinking they easy drift cars they sadly mistaken mate, they much harder than most cars modded to drift spec like SX's or whatnot.
They cult cars, cool as fuck, classics, but not cause they better at drifting than others, far from it, they dead hard to drift well, esp at speed (i mean 3rd gear upwards) due to the lack of power, so when you good in one, very rewarding.
But you very rarely see 86s winning competitions, and thats for a reason.

Regarding AE86 prices, now they getting more common over here the price is settling down at last, heres a thread about prices, and the people commenting are long time 86 owners, so know the crack...
http://www.driftworks.com/forum/showthread.php?t=28031