Is the construction project feasible or are we taking on more than we can handle?

If you are going to become parents in 5 months and still have no financing, by the way, you can’t hide that from the bank either. It’s becoming obvious, you would have to meet a very old bachelor who has never heard of pregnancies... every bank advisorin immediately sees what’s going on.

There are banks today that you don’t even have to go to anymore.
So if you want to, you can keep it a secret. And a bank you don’t have to visit won’t find out later either.
Whether that’s wise is up to you to decide. I would only do it if I were absolutely sure that I would get a job after parental leave.

Did you adjust your tax classes in time so that the parental allowance is as high as possible? Be careful, the parental allowance is paid out under the progression clause. That means it has to be taxed retrospectively like "normal" income in the income tax return, thus increasing your taxable household income and reducing your monthly budget or leading to a hefty additional payment if during the period of receiving parental allowance the earner has tax class 3, because then the tax "prepayment" is already low while the parental allowance (still) is not yet subject to taxation.

Be careful, parental allowance is paid out under the progression proviso.

That is correct

That means it has to be taxed like "normal" income in the income tax return,

That is not really true. It is included when calculating the tax rate for the remaining income, but no taxes are due on the parental allowance itself. (The notes on this are correct – don’t completely forget that there may still be an additional payment)

Therefore, it is best to simply switch early enough if it fits financially and then keep the [Lohnsteuerkombination] during the reference period or switch to 4/4. Switching to 3/5 often leads to additional payments; if you keep it, then usually not, or even rather a refund. You just have to take a look, also whether the switch beforehand is worthwhile (depending on wages).

Where a few hundred euros don't make much difference with a net income of 5,000, at best it's just a bit more money to go out to eat or buy decorations. The trick only works if you know about the pregnancy by the 2nd month at the latest and switch or have already switched beforehand. In the end, you have to switch when you start to "practice"...

Even if you do it online with a bank, you should hurry. Maternity leave starts 8 weeks before birth, and this is also visible on the payslips because the employer does not pay the full salary during maternity leave.

Although a few hundred euros don't make much difference on 5,000 net, at best that's just a little extra money for going out to eat or buying decorations. The trick only works if you find out about the pregnancy by the 2nd month at the latest and switch or have already switched before. In the end, you have to switch when you start to "practice"...

Even if you do it online with a bank, you should hurry. Maternity leave begins 8 weeks before birth, and this will also be visible on the pay statements because the employer does not pay the full salary during maternity leave.

it also works in the 3rd month or possibly in the 4th month if you forgo excluding maternity leave. For a couple around 30 without children, the bank will include a pregnancy anyway. Anything else would be negligent...