Gardener only mentions net prices

The question is to what extent you can really set fixed prices for all these additional works exactly? Or are these prices simply reflected in the invoice now, only that VAT is then added? So, for example, the trees with 405€ would then be 405€ + VAT?

The exact prices discussed via WhatsApp or verbally can be found, labeled as flat rates in the invoice.

Then there are no justified costs according to the cost estimate either. The landscape gardener simply messed up. And if it can at least partially be proven via WhatsApp protocol, you certainly also have good chances with the verbally agreed prices.

What does your landscape gardener say about it now anyway?

well, the biggest chunk was curb stones and L-stones, as well as additional paving of the sidewalks in front of the house.

That sounds like the matter but by no means like surprising increases (???)

well, the idea came up during the work when the excavator tore up all the curbstones. Otherwise, it would have looked silly ;)