God will provide. What you NEED, not necessarily what you want. And going back to that discussion on Human Respect -- God won't shield you from having to be humble -- pick up (perfectly good) things being given/thrown away, accepting donations, hand-me-downs, etc. Why would God shield you from an opportunity to practice such an important virtue?
My wife and I intentionally lived below our means for many years, basically "pretending" we were poorer than we were, at least according to the world's standards. What I'm saying is: if you decide debt is not an option, you seem that much "poorer" to the average Modern. If you need to have a few thousand cushion and no debt, you say "I'm broke" or at least "We can't afford that." but for most people that would mean their credit card limit has been reached!
But yes, those worldly "calculators" and foolishness that passes for wisdom -- that's an obvious attempt to discourage and propagandize Trad Catholics from having the family and children God would send them.
I've seldom made more than $50K annually my entire LIFE -- just 3 years did my income exceed that. We have 9 children and acreage (not in the boonies either). My only "secrets" have been: debt-free lifestyle, diligence (hard work), frugality, and maybe the natural brains/talent that got me a $50K-ish income without college. We don't even know what a cut-off notice LOOKS LIKE from any of our utilities. We have lived a frugal and debt-free lifestyle from the beginning.
I credit Thomas A. Nelson for teaching me about the true nature of money, debt, the JQ, etc. when I was a young teen during catechism classes. I realized that if I wanted to live like no one else (wife staying at home, having a large family, etc.) then I'd have to do something different than the average Joe. SOMETHING would have to give. Either I had to win the lottery, or do something else to set myself apart. You don't get to be "special" just because your Mom loves you. Everyone has that. You need to have something going for you, something different, that says that YOU get to be the lucky guy whose wife gets to stay home, and raise a much larger family than most. Frugality and consistent living below-my-means was that "something different".
A young couple really has to treat it like a war, a game, or something along those lines. You have to be wise as serpents. Be clever, find ways to fix things, save money, do with less, and what not. You have to put some effort into it, but it's WELL WORTH IT.
I can't emphasize enough the importance of choosing a GOOD, VIRTUOUS, FRUGAL woman for your wife. That's got to be a huge cross for many guys -- you work hard slaving for the man, and she spends on on "stupid s****". So many modern women do, including many Catholics and even Trad Catholics I'm sure. Too many clothes, shoes, MAKEUP, Jєωelry, travel, and countless other ways to fritter away your resources. Yes, a frugal, down-to-earth woman is a HUGE blessing, and MORE THAN MAKES UP for lots of perfect figure and symmetrical face. I'm saying "If you wanna be happy for the rest of your life, never make a pretty woman your wife..." Choose a woman that isn't so hotly contested for. She'll keep you happier, take better care of the household and children -- you'll be much happier in the end, trust me. Looks fade.
God provides differently for each person. Some he provides brains. Some, skills. Some, luck. Some, family and/or friends. Some, inheritance. Some, ambition/drive/a good career. Some, diligence. At any rate, you're not going to starve if you trust in God and do His will. Just be prudent. God gave you a brain and a body capable of X amount of work and diligence. Use that TIME and ENERGY wisely to arrange your life rationally and intelligently. Be a human, not an animal.