The 1956 Chevrolet Bel-Air was offered in 7 body styles (original base prices in parenthesis): Nomad ($2,608), Beauville wagon ($2,482), convertible ($2,344), Sport Sedan ($2,230), Sport Coupe ($2,176), four door sedan ($2,068), and two-door sedan ($2,025).
Value today is completely dependent on body style, condition, options, and color. A basket-case 4-door sedan would be worth barely $1,000, while a flawlessly restored convertible with all the desirable options and color schemes could fetch upwards of $100,000. In January, 2006, a '56 Bel-Air convertible sold at auction (Barrett-Jackson) for $106,920. (http://www.barrett-jackson.com/auctionresults/common/cardetail.asp?id=178760)
Generally, the most valuable bodystyles are the Nomad, Sport Coupe, and convertible.
Engine choices for all included a 235.5 cubic inch straight six that produced 140 SAE Gross HP; and a 265 cubic inch small block V8 available in various outputs: 162hp, 170hp, 205hp, & 225hp.
Standard and Optional features for 1956 (partial list):