Dynamic Ad Insertion & Audio Cleanup

I need help with two main tasks for my audio files: 1. Inserting dynamic midroll ads that change over time. This requires finding appropriate places to insert markers within the files, approximately every 15-20 minutes... (Budget: $250 - $750 USD, Jobs: Adobe Audition, Audio Editing, Audio Engineering, Audio Processing, Audio Production, Audio Services, Music, Podcasting, Sound Design, Sound Engineering)