* Inheritance: They received a significant sum of money from their mother, Molly Weasley, as part of her inheritance from her own mother, which she specifically designated for them to start their business.
* Savings: They had been saving money from various sources, including their earnings from their joke-making ventures, and potentially some gifts from their family.
* Investments: They likely invested some of their savings in various ventures and possibly received returns on those investments.
* Loans: It's plausible they obtained a loan from a bank or a family member to supplement their initial funds.
However, it's crucial to note that the exact source of their initial capital is not explicitly stated in the books. The primary focus is on their entrepreneurial spirit, their creativity, and their dedication to making their dream a reality.