Jack Leimbach, a college student and entrepreneur, makes around $10k a month with his window washing side hustle, which he started with a simple $200 kit. He shares his journey, from overcoming initial challenges to leveraging targeted online ads that dramatically boosted his revenue. Jack highlights the importance of client relationships and effective marketing strategies, including impactful video ads. He also discusses balancing academic life with business, underscoring the potential for significant income through discipline and smart planning.