Buying new apartment ("Neubau") in Vienna

I'm considering moving to Vienna next year, and also buying an apartment. I prefer buying apartments that are brand new. Are the listed prices of such apartments fixed, or is it normal to negotiate property prices in Austria?

Example:

https://triiiple.at/wohnungsfinder/#livingArea=[43,102]&rooms=[2,4]&price=[269000,1000000]&level=[]&direction=[]&tower=2&order=price

This LINK will explain all you need to know.