1930 Alfa Romeo 6C 1750 GS Spider 4th Series 29 March 2017 1930 Alfa Romeo 6C 1750 GS Spider 4th Series Highest Bid: €1,850,000 Auction: RM Sotheby’s Villa Erba 2017 Estimate: €2.200.000-€2.600.000 Tim Scott ©2017 Courtesy of RM Sotheby’s