Hi Phipps,
see my reply to your other post on this subject - I believe that the 'Roberts and Son' you mention was my GGrandfather's firm, Ivor L Roberts, who was a dealer in Renault motorcars in Swansea's Oxford Street in the the 1910s, 20s and 30s. he also sold many other makes of motorbicycles and cars, but Renault was his main car manufacturer.
Lizholt