Pricing is always subjective but from what I've seen and naturally Just my opinion
Spiderman depending on condition and Variant
with any kind of run in the outfit $20-$25
good condition outfit $35-$45
Red torso Spiderman $50-$60
Sewn on Sleeve Spiderman $90-$100
Circle suit Spiderman $300-$400
Diamond Suit and Broken suit $$$ unknow big bucks $$$
Robin
Removable mask robin all original $900-$1100
Removable mask robin reproduction mask $250-$350
Painted mask robin with elastic belt all original $80-$100
Painted mask robin with plastic belt all original $50-$60
Painted mask robin with plastic belt cloth emblem plastic snap all original $100-$110