The car was built of a unibody construction, making restoration difficult for cars that were kept in rust-prone climates. The basic design of the 356 remained the same throughout its lifespan, with evolutionary, functional improvements rather than annual superficial styling changes. Nevertheless, a variety of models in both coupé and convertible forms were produced from 1948 through 1965. One of the most desirable collector models is the 356 "Speedster", introduced in late 1954 after Max Hoffman advised the company that a lower-cost, somewhat spartan open-top version could sell well in the American market. With its low, raked windscreen (which could be removed for weekend racing), bucket seats and minimal folding top, the Speedster was an instant hit, especially in Southern California.
It was replaced in late 1958 by the "convertible D" model. It featured a taller, more practical windshield (allowing improved headroom with the top erected), roll-up glass side-windows and more comfortable seats. The following year the 356 B "roadster" convertible replaced the D model but the sports car market's love affair with top-down motoring was fading; soft-top 356 model sales declined significantly in the early 1960s.
Cabriolet models (convertibles with a full windshield and padded top) were offered from the start, and in the early 1950s sometimes comprised over 50% of total production. A unique "Karmann hardtop" or "notchback" 356 B model was produced in 1961 and 1962, essentially a cabriolet-style body with a permanent metal roof.