Overnight ~500€ more saved monthly? I would sharpen the pencil again. When you have two numbers, always calculate with the smaller one when it comes to budget or round down.
First, get clear in principle about your current income and expenses.
A household budget book can help with that. Since I personally am not a fan of such things, I evaluated the bank statements of the last 18 months. That's not 100% accurate because I sometimes buy cigarettes at the gas station, but it is brutally honest. But that only works if you pay 99.99% by card.
If you are planning to have children: There are so many unknowns that expenses cannot be quantified. It starts with breastfeeding (being able to) or buying expensive milk and ends, at least in the first years, with childcare costs. In our case (childcare until 2 pm including lunch) that is about 350€, over 500€ per month until 4 pm.
And we were very lucky there. There were no day mothers left in our town, the local kindergarten offers care from 8 am to 1 pm. When and where should one work there? Fortunately, our daughter only attended there for 2 months until the acceptance from the kindergarten in the neighboring town came (but only because the parents-in-law live there and we will be building there next year). Otherwise, my wife could not even have taken a part-time job. We registered her in the kindergartens when she was less than a week old (so 2 years in advance). And even today my wife can only work that long (35h/week) because she works only 3 minutes by car from the kindergarten, grandma is 2 minutes away on foot and picks up and drops off our daughter twice a week, and although I need 60 minutes to get to the office, I only have a 34h/week schedule and can come and go very flexibly.
Oops, got off track, but what I want to get at is that you simply do not know many things beforehand, and things can really turn out badly differently. Especially if you are already planning to have children, it might indeed be better to postpone the purchase, at least in this travel region.