Note: In France we had an additional problem in that our TVs were [https://en.wikipedia.org/wiki/SECAM SECAM] only in the 80s. A monitor was required for foreign computers like the C64 PAL or the ZX Spectrum that didn't output RGB. TVs only became PAL/SECAM compatible in the 90s.
The minimum wage in France in 11/1984 was at 4116 Francs per month for a full-time job. Source: http://www.cda-strasbourg.org/smic.htm
In June 1985, the CPC 664 was launched at 4490 Francs for monochrome and 5990 Francs for colour. Source: Micro 7 #28 - 06/1985