I've been posting here for 15 years. Its interesting how the bass playing culture has changed during that period.
The string boiling/soaking topic was once a top 20 recurring discussion around here, because people's tone goals were different than they mostly are today. Now it only comes up periodically.
Anyway, denatured alcohol is the way to go. I'm a hardcore experimenter all my life in this area, and in my experience the alcohol approach is about 40% more effective than boiling. Easier, too.
Here's what you do.
This is a picture of my string soaking tube:
View attachment 3852234
Go to Home Depot or Lowe's and buy a 4 foot PVC tube like this one, along with two matching caps. The caps seal pretty well, but you might want to get a tube of PVC joint adhesive to fortify the bottom cap. The whole order will cost under $20.
Fill it with denatured alcohol. Slide your strings into the top and cap it off. Leave 'em there a day or two, then pull 'em out, dry off, and reinstall or store. Great results.
I drilled a hole in the top cap and screwed in a cupholder hook (and sealed around the hole) so there would be something to hang the strings from inside. Really though, they tend to stand up on their own in there and aren't hard to just fish out.
Big fat claim. I gig about 20 nights a year, so "some but not much." I have sets of strings on a couple basses that I've kept going for 7 or 8 years this way, and they still sound great.