Please identify this car for a point
Mercedes Benz?
no
Experts?
Professionals?
German?
apparently yes
Perhaps an Aga?
no
Dehn?
Lauer?
not a Dehn or Lauer
From a short-lived marque (<= 5 years)?
Oops, apparently not, this is not German. Sorry for misleading you
Austrian?
yes
ESA (Egon Seilnacht, Atzgersdorf)?
yes
Georgano says that ESA started in 1920 with pointed radiators and turned to flat radiators in 1922. If that is right, it should be older than "cca 1924". The car also looks rather like the early ESA 8 PS than the later four-cylinder ESAs. Or does your source reveal more information?
you are right, I update the heading
A racing version of the ESA:
Ready to depart: