Price for grassland behind the own property

Hello,

Behind our house, there is a strip of grassland along a stretch of about 4 house plots, estimated to be 70 meters long and 30 meters deep. Behind that comes the cemetery, so the strip will never be buildable.
The only building on the green strip is a small wooden barn behind our property as an existing building, estimated to be 6x8 meters.

Two of my neighbors have leased about 20 meters deep of the strip along their property width. For another property, a third-party tenant has leased about 20 meters deep. When the others leased the properties additionally, it was said that the property will not be sold but can only be leased. I did not inquire about the lease since the barn is behind our property. For me, the property would be more attractive than the part with the barn.

The properties are farmed by an elderly couple, who are still quite active but are probably approaching 80 years old. Besides some grapes by the barn and a few raspberry bushes, the rest of the property is mainly used for making hay. Occasionally, in the past years, the son’s sheep have been on the property and in the barn.
The son himself has a house and properties a few places away.

It feels like the property will eventually become more a burden than a benefit for the couple. The property probably brings little benefit to the son himself, at most if the grandchildren should move into the grandparents' house. (The residential house is about 200-300 meters away from the green strip.)
Before anyone unknown acquires the property, I would still like to make an offer to buy, possibly for the entire area under assumption of the existing lease contracts. Only, I have absolutely no idea what to offer for it.

The current standard land value is 8€/m². A few years ago, I think it was still 4€/m².
Building land prices were about 90 €/m² seven years ago, the current standard land value here is 125€/m², and in the newly developed residential area in town, prices were 220-250€/m².

For better understanding:



On the left, the white-gray area is the cemetery, the yellow "T" is the remaining property, and blue is the leased portion. Of that, the upper part is leased to third parties, and the two houses below have leased the part behind it. While cropping, I just noticed that the entire property spans over 5 plots, approximately 88x30m.

So I would always ask what someone wants before I give a price, usually I have made more bargains that way. When inquiring about a purchase, you can argue with the care, etc.

With 25-30 k you will probably be allowed to calculate.

Depends on whether it is an indoor area and land designated for development or an outdoor area.

Well, I would always ask first what someone wants before I say a price, most of the time I made more bargains that way.

Mhh. You may be right. In terms of price, you can probably make more of a bargain that way. On the other hand, you don’t know if their price expectations are realistic and maybe they think they’ll only get 5€ for it and prefer not to sell at all.