As you may know, $1 at McD is cheap but certainly not healthy. You wouldn't do that for 2-3 meals/day x 30 days/month either (someone has already documentary-filmed that). Have you checked out r/EatCheapAndHealthy or r/Frugal or similar resources?

I ran my numbers for 7 years of expenses as a single person (extrapolating 2022 YTD to the full year) and found that groceries are 70-80% of my food spending. Social is about 15-25% (includes some general entertainment but it's mostly food) and the rest is self-dining/takeout. I realize this is a bit extreme but maybe you can calculate your current grocery percentage and work on getting halfway to mine. It does takes time to plan, shop, cook, clean (and I store and eat leftovers, rather than simply cook "one serving" at a time) vs. it takes money to pay for the convenience of eating out, which is someone else doing all of that for you.

3.5% down on 129k is about 4.5k. I'm not thoroughly reality-checking all the numbers (and also I personally would not do 3.5% only) but I just have the impression that the upcoming months might be good for seasonal work. Can you hustle and make a dent in that? Or make a dent in the car loan - and once you get rid of the car loan, that few hundred dollars of monthly payment can go towards your house fund.

Keep in mind that with a mortgage, the bank "owns" your home, and if you don't pay, you will eventually no longer own it. When the mortgage is paid off, you still have property taxes, and if you don't pay, you will eventually no longer own it. All throughout, anything that needs maintaining or fixing - anything that you previously called the landlord about - is all your financial and emotional responsibility! I'm not saying don't dream, or be fearful of everything, but do go in with a plan knowing the practical realities, not only a starry-eyed ideal.