Valuation of farmland for development into building land

That's actually how I see it too, but in my case and with the luck I have, it won't be that easy. Because everyone there now obviously smells a business opportunity. If it becomes too expensive for the investor, then the landowners will be stuck with it and he will build around the plots.

Yes, that will be the case. Why wouldn't it be that easy for you? I don't quite understand the sentence. Ultimately, I know examples where landowners were too greedy and then it simply didn't sell. The dangerous intersection remains dangerous, the development area won't happen.

According to your idea, you are getting a complete star pastry shop. And for the buyer, you have months of rotting fish in front of you. Think about my potential calculation. By the way, the purchase price can also be linked to a promissory note by utilizing the property or land value increases. Get some advice.

Sorry, what is a promissory note supposed to be? The fact is, and I understand that one wants to make a profit, that I don’t want to give it away. A house is being built on it and 450K€ was given for the land at 30€/sqm.

You cannot demand the same price for a field as for a piece of developed building land in the same location. Somehow I gather that this is your wish. Naturally, that will not work.

Talk to the investor. Financially participate in the renovation of your space as part of the investment. When selling the building land, you will then receive your fair share of the profit.

It has already been said: if you don't agree on the deal, then that's just how it is. And I boldly assume that you are not dependent on the money. If that is the case, then keep the land and don't let yourself be pressured. You can only sell once. It is true that the investor will pour a lot of money in before anything happens. However, after three years, he will certainly not walk away with just 500k plus. If building plots are really needed, the municipality should buy the land and sell the plots cheaply to families in a fair process. If they don't want to = not your problem. You have no responsibility here, but only by chance own the land. If the price is too low for you, then don’t sell.

If you assume only €40/sqm, I will do it that way. That will probably be the best.
Thanks for the tip.
I also have no problem with swapping the location of the property and marketing it myself.
But I definitely will not give it away.
That will be a difficult negotiation.