I use store bought olive oil from our local Walmart & Sam's club here since we don't have a Costco or Kirklands. I've never had a problem! I've been soaping for over 4 years since re-starting after a hiatus for a few years.
I keep my main soaping supplies on a cart. That way I'm not gathering them each time. I do like others have mentioned above, except master batching. Moving everything to a sink of hot water as soon as I'm finished with each item helps me stay focused too.