Cheap Apartments For Rent In St Charles . Find top cheap apartments for rent in st. The average home rent in this town is $1,160. S 10th Street Apartments for Rent S 10th St, St. Louis, MO 63102 Zumper from www.zumper.com As of june 2021, the average apartment rent in saint charles, mo is $822 for a studio, $929 for one bedroom, $1,108 for two bedrooms, and $1,331 for three bedrooms. As of june 2022, the average apartment rent in saint charles, mo is $1,097 for a studio, $937 for one bedroom, $1,282 for two bedrooms, and $1,568 for three bedrooms. Rent.com® offers 382 cheap apartments for rent in saint charles, mo neighborhoods.