Is the dream of a home realistic with our financing?

What does the m2 floor usually cost in your desired area? (Bodenrichtwert)

Please be careful with such assumptions... everything included is what is stated in the contract, which by far does not have to be everything... phrases like "16 cm floor slab or according to static calculations," "earthworks up to 30 cm," "high-quality branded tiles," "a comprehensive electrical installation"... but also the absence of a construction toilet, site setup, or debris removal can potentially lead to unpleasant surprises.
Have contracts and construction service descriptions checked.

*Edit* just noticed - this is a BT... well, then some of my comments no longer apply.

If a net income of 3200 and equity of 20000 are too little for a house including land, I seem to be in the wrong forum here. After deducting all living expenses, we have 1700 euros left. A rate of 1000 euros or more would also be no problem.

Not the wrong forum. Wrong time? Wrong country? Wrong income? Pick one. Be glad that people here speak "plain talk" and you don't have a banker in front of you who sugarcoats the numbers.

3200 EUR is (as family income) quite below average and with that I wouldn't build a house today. Not even 110 sqm. Especially not without equity.

I have it in the family: income was about 3500 EUR. House 110 sqm, equity was about -10,000 EUR (was included in the house financing). Turnkey built... oops... there are still 20,000 EUR missing for walls and floors... also another 20,000 EUR for kitchen, moving, miscellaneous... also, damn, the exterior facilities are still there. Result: 2 years after moving in, moving out with a visit to the PI.

My word for Sunday.

Vista is a property developer – so the risk is somewhat more limited. However, cost items mentioned by Steffen must be strictly observed and included!!

with the Vista house, everything is all inclusive

I just want to point out that you should (not only) take a closer look and read carefully when it comes to offers for houses.

When I read on the Vista homepage under special equipment that you can order a hot water connection in the kitchen as well as the guest WC separately, of course only in the Vista-Comfort package, the prospective buyer should ask themselves what else is actually included in a house.

Basically, you probably also have to do the painting and floor laying yourself at Vista – materials too, of course.
The additional purchase costs will then bring the €177,000 domicile roughly to €200,000/210,000 – then you have basic standard (according to the offer) without a kitchen.
Complaints about too few sockets and the washbasin in front of the saving bathtub come free of charge.

Basically, however, the terraced house is an alternative to renting an apartment. However, I would consider whether for such a house with stairs and narrow corridors, higher monthly ancillary costs, and very close neighbors with children, of whom there will be many in the Quarre, you want to sacrifice your pension.
Since we are also the same age, I know that the stairs will eventually become a burden and that noise from the dense next-door neighbors (which I also had in the terraced house) can be nerve-wracking.

Building a house within the budget is probably not possible, a used property will certainly fit, depending on what concessions one is willing to make. We have less income and fulfilled the dream without any further problems. Our equity was under 10,000 and was enough for the ancillary purchase costs (7,000 euros), that was it. The installments for the house are lower than the rent before. In return, there are higher travel costs, it roughly balances out. The additional costs have remained the same. You can save quite a bit of money when buying a used property, provided the property has decent condition and you can and want to do a lot yourself - and maybe not everything has to be brand new immediately. But the house has to fit, and here the factor of luck comes into play. Is the desired house currently available on the market in the right size, location, and equipment? Are you willing to search for 1-x years if necessary or does it have to be right now?