Nice !
I too am surprised at the low cost, but then I'm sure it was a LOT of work. I know, because I did one of these before, though the set up was different. I recall "learning" alot along the way. The next one will incorporate all of the learnings (mistakes I made) from the first one.
At the time I was in a hurry because I had clients lined up and practicaly pre-booked time , so getting it done was more important than doing it right. Looks like you time you needed. Looking at all of those photos on the blog bring back memories (the caulk, the drywall, the wiring, the "if water can get in so can air" attitude I had .....).
I'll be doing it again at some point in the next year or so when I get the right property (may well end up being an old stone house - lots of those here in France).
Actually loved it .....can't wait to break out that hammer again
Regards ....