The Rolleiflex 3.5 F Prototype is a 6x6 medium format twin-lens reflex camera from Rollei's post-war TLR line. As a pre-production example of the 3.5 F, it sits outside the standard production run and is of interest primarily to collectors of Rolleiflex development history.

Hammer prices at UK auction for this prototype are based on a very thin record: a single saleroom result of £1,500 in 2008 is the only verified data point, so today's market value cannot be triangulated from a meaningful range or median. Prototype Rolleiflex bodies are condition- and provenance-sensitive, and what a 3.5 F Prototype is worth in 2026 will depend heavily on documentation and the depth of bidding on the day rather than any settled price band.