When deciding between a Solo 401k vs SEP IRA or comparing a SEP vs Individual 401k, understanding the features of each plan is crucial. Solo 401k is designed for self-employed individuals, offering higher contribution limits and optional loans. On the other hand, SEP IRA is a simple, flexible option, especially for small business owners with employees. Key factors like ease of setup, tax benefits, and contribution caps can guide your decision. By evaluating these differences, you can choose the plan that aligns with your financial goals and maximizes retirement savings effectively, ensuring a secure financial future.