I started doing this myself after getting sick of price increases on NaOH. Not to mention dealing with paranoid shippers charging outrageously high hazmat fees.
Anyway, when NaHCO3 gets to the proper temperature, it'll literally bubble (especially if you stir it). It looks like air bubbling up through wet sand at the beach. When it stops bubbling, it's done. Na2CO3 looks a little more grayish than NaHCO3, and is a little bit more free-flowing.
As for the Ca(OH)2, you can still easily that at any grocery store. I buy MrsWAGES pickling lime from the canning section. It's a big, green, 16oz HDPE canister an costs around $4 where I live. There are a few brands that have additives, but the one above is 100% food-grade hydrated lime. I see it everywhere. Guess that means nobody's figured out how to make an illegal substance with it yet. :/
Kel