Costs for purchasing land in a new development area

Good evening, I need assistance with the purchase of a property.

The property is located in Lower Saxony, near Göttingen, and is being sold by the municipality.
The property is 834m2 in size, today we received the following in the mailbox:

1. Redemption agreement
Redemption of connection fees
Calculation of the water supply contribution 1,060.30€
Calculation of the wastewater contribution for sewage disposal 1,445.55€

Question:
Are the costs settled with this or could additional costs, e.g. for the road, still arise after a few years?

2. Property purchase contract with conveyance

Purchase price for the property 27,194.15€ (development costs are included in the purchase price)
However, the buyers are obliged to pay an additional one-time reimbursement of costs to the city for the already existing handover shaft (sewage) in the amount of 1,124.84€.
Total price 28,318.99€
I find it strange that we have a redemption agreement once and then the handover shaft costs are added again in the purchase contract. I will try to clarify this with the office next week.

Questions:
On which amount are the notary fees and property transfer tax calculated? 27,194.15€ or 28,318.99€
We are paying for the property in "cash" and currently, the buyers are myself and my partner in the purchase contract, each owning 1/2. Does this mean higher notary fees? Would it be better if only one partner is listed? (Marriage will happen later...)
I somehow can’t find an exact calculator for the total costs online... if I’m just not good at using Google, please just say so.

Thank you very much in advance!

€28,000 for such a large plot of land I wouldn't care about these peanuts.

Down here (Stuttgart) something like that costs at least €450,000....

Regarding the question, do notary fees apply to the purchase contract amount or not?! Since it is calculated as a percentage (1.5%?!), it doesn't matter how much you divide it.

Regards

And clarify what is happening with the development contribution for the street, which is still missing in the statement. That quickly becomes 20€ per square meter and more.

So in NRW, you pay alone for the development (sewer, road, etc.) in the new development area 70,000 € for the plot size. How can the city offer the plots so cheaply including development costs?

How can the city offer the plots so cheaply including development costs?

It's just in the middle of nowhere. Maybe there are already old sewers (that's how it reads).

Notary fees? Would it be better if only one partner is listed?

In the land register?
The person listed in the land register is also the sole owner.
Even if you build a house together on it, everything belongs to the one listed in the land register.