House purchase foreclosure auction - What price is realistic

Well, the terminology does confuse you a bit. It's not really my area of expertise, but just to sort it out.
He paid 100,000 EUR for the property back then, but it was still burdened with a liability of 45,000 EUR? And the market value he determined of 75,000 EUR already took this liability into account?
Then you first have to note that the pure market value was 120,000 EUR.
How much tax he paid or has to pay has nothing to do with the market value. That he would like to have it is his business.
However, if you say he could now easily get 200,000 EUR for the house, then that is the market value.
Whether you like it or not. Whether one believes the current market value is too high for whatever reason is another matter.
You also have to be cautious with appraisals. There are different approaches to determination. And if the appraisal were to determine 170,000 EUR but the seller has several offers at 200,000 EUR, then the market value is still 200,000 EUR.

And again, what is behind this fiscally is completely irrelevant to you. What are you willing to pay? You can tell him that. If he wants more and also gets it... then so be it. But neither the seller’s tax changes anything, nor does it influence the value in any way.

And just by the way, I cannot judge the numbers by their scale. 24 EUR/sqm, 200,000 EUR for a house that is in good condition, and for a little more you can build new. That is so far from the prices in my region (BW) that I cannot make a judgment. I am just amazed.

200TEUR for a house that is in good condition and for a little more you should build new. That is so far from the prices in my region (BW) that I cannot make a judgment.

True, in "normal" regions and larger cities that already costs the land... (except boom regions, where you either get no land or only a tiny piece)

Don't be surprised, I created my own account this morning, the other one is through my brother.. That's why there are 2 different ones.. I think I mixed up the terms market value and fair value.

He paid 100TEUR for the property back then, but it was still encumbered with a liability of 45TEUR? And the fair value of 75TEUR he determined already took this liability into account? Then one must first note that the pure fair value was 120TEUR.

That should be correct. So he paid about 20-30 more than the fair value. What we are willing to pay we have to see. Our plots are really "still" cheap here, but not for much longer. 5km further it already looks different again. Nevertheless, we have to weigh whether we want to build or take something used. The fact is, we won't get a house like that again so quickly.. Unfortunately, this will also affect the price! However, compared to other prices in Germany, this one seems really good..

I think I confused the terms market value and fair market value.

They both mean the same thing - so you can't confuse them.

They both mean the same - so you can't confuse them

Ask okay Also the value calculated by the land registry office for this property is between 110 and 130k for this region..

Don't understand what taxes have to do with the selling price? Taxes have to be paid (if at all) only on the profit, roughly the difference between the purchase price and the selling price (plus additional costs, etc.). Or do you mean that he wants to sell more expensively than he bought because he also paid real estate transfer tax? That can't have been that high given the amounts.