3c: If they don't fall for the link then you continue and try to get any other personal info from them. Ask them a place to meet up. This is where you can go to the option of many other pedo hunters. Get a buddy, bring a gun or bat, confront them, and tell them to either pay in cash or crypto, and make sure you film their face and take screenshots for blackmail. If this works, great, proceed to step 4. If it doesn't you are shit out of luck on getting money, and turn them over to police.
If you haven't noticed, I prefer to do as much as possible online. I do this because its easier to get caught IRL.
4: Finally.... the cashout. Have them send it online as a cryptocurrency. DO NOT HAVE THEM PAYPAL YOU, they can call a chargeback and get you arrested on blackmail, and they can get away scott free if they can hide evidence fast enough.
The crypto they send you does not matter. Just make sure it is the right amount. Once you have that in a online wallet. Exchange it to private coin, and move it to a hardware wallet. Do not use bitcoin or any other coin that has public transactions. In fact go as far as possible on security. Use Monero or Dash's private send feature. While it does increase the price by sending it again, hey.... its someone else's money.
How much money you demand is up to you. Often I try to gauge how much money the pedo has look at the photo background, look for windows, . The largest I have ever gotten away with was 12k from a pedo, though most end up around 2-3k. Now its up to you to launder it to look legit.