Act as a startup consultant with 10+ years of experience guiding early-stage companies. Provide a detailed list of the best tools for implementing the Lean Startup methodology, specifically tailored for [TYPE OF STARTUP, e.g., SaaS, e-commerce, or hardware]. Include tools for [KEY AREAS, e.g., customer validation, MVP development, and growth hacking], and explain how each tool aligns with Lean Startup principles like Build-Measure-Learn and iterative development. Additionally, highlight [BUDGET-FRIENDLY or ENTERPRISE-GRADE] options, and include any free or open-source alternatives. Ensure the recommendations are actionable and suitable for founders with [LEVEL OF EXPERIENCE, e.g., beginners or seasoned entrepreneurs].