How much time would the whole process take me?
Just remember this extremely important thing:
Don't screw up.
Seriously, it's risky if you don't follow the guide exactly. Although, it has been getting
way safer than it used to be. I know that from experience because I followed the first ever guide to dump my OTP and figured out how to install A9LH myself, because that wasn't part of the guide. Recently, I followed the most up-to-date guide to dump my otp0x108 (I believe that was it), and I noticed it had the
full guide, rather than just the guide for OTP! Meaning,
all of the previously-assumed to be completed preparation, plus how to compile and install A9LH, which isn't even necessary anymore because of SafeA9LHInstaller!
Oh, how the times have changed!