There are several sources of financing available for businesses at different stages of growth, including equity financing through sources like seed funds, business angels, and venture capital funds, as well as loan financing from banks. Equity financing provides ownership in exchange for risk, while loans require interest payments and repayment but provide no ownership. Public sector financing through grants can also be an option. The type of financing needed depends on the business lifecycle stage, with seed capital and public grants used for R&D, business angels and venture capital for startups, and bank loans and equity funds for later stage growth.