Your estimates are WAY off.
Base sticker prices (US Dollars, unadjusted):
1986.5 Model Year
N/A - $19,660
1987 Model Year
N/A - $20,490
Turbo - $23,595
1988 Model Year
N/A - $21,740
Turbo - $24,210
1989 Model Year
N/A - $22,360
Turbo - $24,700
1990 Model Year
N/A - $22,860
Turbo - $25,200...