There are various techniques that startups can use to reduce their customer acquisition costs. One way is by leveraging social media and other digital marketing channels that offer cost-effective ways to reach potential customers. Another technique is to optimize the customer acquisition funnel, ensuring that each stage is as efficient as possible. This can be achieved by investing in analytics and conducting regular A/B testing to determine areas where improvements can be made. Additionally, businesses should focus on developing relationships with their customers instead of relying solely on traditional marketing methods such as cold-calling or email campaigns. With the right strategy, startups can dramatically reduce their CAC and achieve massive success.