"20th century German School" is work by Wilhelm Hambüchen

Horta, from Belgium, sell on 22 May 2017 a "German School, 20th century" boats, a small (20 by 26) oil on panel estimated at 250 to 350 Euro.

With some effort the signature can be deciphered to read "W. Hambüchen", short for Wilhelm Hambuchen (1869-1939), a known marine painter from Düsseldorf. It isn't unusual for German paintings to appear in Belgium (and vice versa), but in the case of Hambüchen it is even less strange as he is known to have traveled in Belgium and produced paintings at and of the Belgian coast.

His works fetch occasionally upwards of 5,000 Euro, but most hover around the 1,000 Euro mark and this is a rather small and not very attractive work, so something in the region of 500 Euro is probably more realistic.

UPDATE: well, it only made 150 Euro, so prople really didn't find it attractive at all, name or no name!