Aaah, there is your mistake
Toyota Corolla AE86
Not Toyota Sprinter AE86...
And yes, the "agreed" value of a 30 year old car (and a corolla at that) is going to be low
Redbook lists the AE86 as a price of $11,738 when brand new... Just exactly how much are you wanting an insurance company to insure your AE86 for?