The OP spent $42,000 (with somehow over a month of work) to install a mini split and then $1000/mo to run it some months just because they couldn’t bother to find the massive leaks in their apartment? Am I on drugs?
There's a related post from the same blog about using Bitcoin mining for space heating. Whatever one may think about Bitcoin, I kinda get the impression that practicality isn't at all high on the author's list.