Complex sentence: Travco enjoyed a large market share of the budding motorhome market, its success played a part in the demise of more established makes such as the Corvair-powered UltraVan, and opened the market to lower cost makes such as Winnebago.
Split into simpler sentences: Travco enjoyed a large market share of the budding motorhome market. Its success played a part in the demise of more established makes such as the Corvair-powered UltraVan, and opened the market to lower-cost makes such as Winnebago.