Where to harvest souls?

I got into the soul trade because I thought it would provide a steady source of souls but it hasn’t so far. Where is the best place to harvest souls?

Unfinished Business in Spite is the best source of souls as far as I know. Before becoming a POSI you can track down a Spirifer in Ladybones Road or rob the Brass Embassy in the Flit.

If you are a spirifer there are a couple of places where you can harvest souls - the first part of the university and if you have rooms at the Royal Beth. I’m not sure if there are any other places.
For souls I like Seeking a thieves cache in the Forgotten Quarter. You either get 400 glim or 500 souls as well as another reward. Just make sure you have enough expedition supplies.

Implausible penance opportunity card -> the smuggler’s grave -> one stone in a thousand (trade 55 cp criminals for 250 souls).
Keep your criminals connection above 15 using old bone skeleton key (trades 3 actions and 150 nevercold brass sliver for 75 cp criminals)
Assuming 100 brass/action (and you can get better than that by educating a louche devil), you pay 3+1.5+75/55 actions for 250*75/55 souls, which is ~ 681.82/5.86=116 ppa. That should be better than unfinished business, on average.

Thanks guys.

Only in this game does a topic with this title seem perfectly normal.