Money advice for families living on one income

I’d love to hear from financial planners, personal finance coaches, etc.) and/or real consumers who are living on one income. Questions:
1. What is the most surprising thing about living on one income that most people might not expect? Is it more possible than people think?
2. How much does daycare cost nowadays, compared to the cost of having one parent stay home? (Can you speak to the phenomenon of how, In many cities, it’s not efficient for both parents to work anymore, since daycare costs so much? Any stats or sources you can cite are welcome here.)
3. For “real people” who are successfully living on one income: What did you give up to live on one income? Was it worth it?
4. What are some good options for parents to earn some extra money on the side without having a full-time job?
5. Any other pros and cons to share, possible long-term risks and downsides, unexpected benefits or things you can take advantage of that make life easier on one income, etc.? Please reply via email first, and then we can follow up via phone if needed. Requirements: U.S.-based Financial planners, personal finance coaches, personal finance experts OR…People who are living on one income who want to share their story of how they made it work (you don’t have to be a “personal finance expert” if you want to share your story)