How Much Should I Be Paying/ Hoping For...

I thought it'd be an idea to start a thread for people interested in figures that available only on the secondary market. This can help with people trying to decide what's a fair price to pay, bid, etc.
I will continually edit this thread with any new replies and credit them accordingly.
I'd like to start with the following:
Suggestions Contributed
1. Revoltech Megatron
USD$20-35
(Thanks to Autobot032, Rushie)
2. Revoltech Optimus Prime
USD$30-40
(Thanks to Autobot032, Rushie)
3. Cybertron Primus
Primus only: USD$50-60
w Unicron Head: USD$60-100
(Thanks to Autobot032, Rushie, Blurrz)
Awaiting Suggestions:
Trypticon (complete and working)
Skystalker
Skyhopper
Groundshaker (those three are micromaster bases)
Action Master Optimus Prime (complete)
SC-22 Takara Omega Supreme
I will continually edit this thread with any new replies and credit them accordingly.
I'd like to start with the following:
Suggestions Contributed
1. Revoltech Megatron
USD$20-35
(Thanks to Autobot032, Rushie)
2. Revoltech Optimus Prime
USD$30-40
(Thanks to Autobot032, Rushie)
3. Cybertron Primus
Primus only: USD$50-60
w Unicron Head: USD$60-100
(Thanks to Autobot032, Rushie, Blurrz)
Awaiting Suggestions:
Trypticon (complete and working)
Skystalker
Skyhopper
Groundshaker (those three are micromaster bases)
Action Master Optimus Prime (complete)
SC-22 Takara Omega Supreme