It's not that hard. We have a modest house purchased pre-covid in the DFW area, one small car payment, no debt and no kids. Our monthly expenses are around 7k/mo and we don't really do anything. Throw in a divorce and a couple of kids, that money evaporates quickly.
I owned my little house in South Florida outright. Little 3/2 on a slab, built in 1961, but it was "luxury" because it was a corner lot and had a two car garage you could park 2 small cars in if you were careful.
Mid-2000s, I decided to take a break from work, so I dialed my expenses WAY back. Property tax was $5k/yr. Insurance (no windstorm) was about $3k per year. Phone (w/ DSL internet)/electric/water was variable depending on the season, but call it $600/mo. Ran the AC at 76. COBRA from the job was $250/mo. Pickled my "nice" car, and just ran with my POS Impreza airport car I'd paid cash for when I was "flush".
Toss in food & gas, I was getting by with about $1,700 in direct, sit down on the 15th and write the check expenses. A few all night shifts at the old man's plant and the $650/mo from my teaching gig at the U, and I was just about treading water.
Just about anything could have blown up my program. This was a single dude living alone. I had substantial savings at that point, reasonably healthy, and was fully insured (minus the windstorm), so I wasn't going to get wiped out if something bad happened, so it wasn't like I was flying without a net, but that's what the numbers crunched out to be.
FWIW, I was covered by a "save our homes" property tax cap, which limited the increase every year. Had I been exposed to the run up in prices pre-market crash in 2008, it would have been a real problem. As it happened, my taxes actually went down substantially when the crash happened, but a lot of people lost their ass by being over leveraged in their home. It was literally like walking out to get the paper in your robe and your coffee, and watching everyone on your block lose their minds running around, and thinking "WTF is going on?".
This period taught me two things you don't toy with....your roof over your head and your health insurance.
"But what about hurricanes?" Yes, that was a risk, but a calculated one. My house was your typical 60's house. Well built, concrete block on a slab. Meant to survive, and had survived a number of storms. The biggest risk factor was the roof. I had spent the money when I was flush to have an engineered, exceed all codes roof put on. I was a bachelor, so all my furniture was worth zero, and anything valuable that I had was kept in water resistant plastic bins, which, as anyone who lives in Florida knows, is the only way to keep things you, well, want to keep. Cost for replacing the roof at the time was $25k, which I had pre-funded and was sitting in an account making money. Why cash? Because again, anyone who's lived in Florida knows, after the blow, the only way to get things done quickly is with Benjies, and my roofer said "if you have cash, I'll be there the next day, because insurance pay outs take forever. You go to the front of the line".
As it happens, Wilma went right down my street. No damage, and other people had tarps on their roofs for 12-18 months.
The 30k foot point I'm trying to make is it is possible, but you need to be dedicated to the program, start ahead of the game, and you need to, in essence, make your own luck to avoid avoidable pitfalls. If you have a family, they need to be on with your program as well.