There is no such thing as a CSID changer which is paid. There is a .pkg file for free for a few CFW ps3's. But you need a legit CSID by yourself and those are hard to find.
There are currently many RTM/RTE tools which have a CSID changer with it btw. BUT STILL U NEED A LEGIT CSID WHICH ARE HARD TO FIND!
True
Nope, maybe with an e3 flasher but that takes a lot of experience and time. You can send it or bring it to places near you which are trusted ps3 jailbreak/repair shops which can install the e3 flasher for you and downgrade your ps3 to 3.55 so you can jailbreak it. BUT there are many different ps3's, some are not able to be downgraded to FW 3.55 or lower. then it's impossible.
What i recommend is to just buy a jailbroken ps3 from a trusted seller.
Ik moet niks, maar kan.
True but hard to find and trust and not always near you.