30 years ago I used t go to weekend 'marathons'. IIRC, the cost was 2X or 3X the cost of an individual session. They were probably worth 10X an individual session, so they were worth the cost. I have a hard time seeing how it would be worth $3,000, though.
IMO, I would never spend so much money to hear someone who doesn't have any counseling experience tell me how to heal my marriage or myself. I would much rather spend it on counseling.
Now, IMAGO retreats, THOSE are something I would happily give thousands to. Licensed counselors, teaches you how to communicate with each other effectively, AND deals with FOO issues. Seriously, if you are in the market for something intense, go to IMAGO. You can even get the books and do it alone at home, or follow up at home after the weekend, and you can even continue to see an IMAGO therapist after you get home too.
We can't afford this, but if we could, I would do it.
Have to say the weekend jumpstarted our healing in the best way. WH got to hear from other BS the same things I had been trying to say, so he realized I was not crazy. You have the benefit of being away from home without all the "stuff" that gets in the way. You have the benefit of one-on-one and group sessions. The weekend moved us 9-12 months ahead in our counseling. Definitely worth the money. They do have scholarships available and there is a money back guarantee (never heard of that with MC). IMO