Generally, most of the models have pretty good ventilation. Particularly if run the overhead fan. Although the one that came with my trailer was rather loud. I swapped it out for a Fantastic Vent that automatically switches on the fan at whatever temperature you set.
Tell us which model your looking at and maybe one someone can give you more specific info.
2011 Chevy Silverado Crew Cab 4X4
2009 210 WBS