I have seen photos of him with a Leica III at some point, or maybe he borrowed Gerda Taro's Leica camera? He is also depicted with a Rolleiflex around his neck at times.
I yet have to see those rumoured photos of him with a Leica III. In spite of owning many books about him, including the original 1946 edition of his "Slightly out of focus" in which the historical truth is deliciously romanced, the closest I have come to, re. Capa having used a Leica, is the caption of his famous photo of Leon Trotsky in Copenhagen in 1932, often said (by mistake, see below) to have been taken with a Leica III. A full series actually. Contact sheet :
©Robert Capa/ICP/Magnum Photos
But - no picture of him with the camera. And the camera was a Leica II, not a III. That black Leica II was put at auction by Westlicht on 11/24/2012 (s/n 90023 with nickel finish Elmar 5cm f/3.5) and sold for 78,000 euros.
The known photos of what is said to be his second Leica, a chrome III with a Summar 5cm f/2, are photos of Gerda Taro using it after he passed it on her after he began using a Contax II.
All the photos of Capa sporting a camera which have come to us show him with a Contax II, a Rolleiflex, a Contax IIa, a Nikon S, a 16mm movie camera, and Linhof & Speed Graphic LF cameras. This is not to say he never used a Leica, because he did actually, until 1937 probably, but, strangely enough, we don't have photos of him using it. Actually when he was still using his Leica II (and, a bit later, his chrome Leica III) he was still the anonymous Endre Ernö Friedmann, not yet the famous Robert Capa : nobody wanted to take a picture of him at that point. His own girlfriend still was the anonymous Gerta Pohorylle, not the famous Gerda Taro.
Here you can listen to the only recording of Capa's voice, in the NBC broadcast "Hi! Jinx" (1947) :
https://www.icp.org/news/robert-capa-1947-radio-interview