Yes, it's not an absolute necessity to pay expenses from a separate business account, especially right when you are starting out. You just need to keep very good records of what business expenses were paid from the account and save receipts. It is advisable to open a separate account before too much time goes by, because it's much easier to show your intent to earn a profit and to track your expenses from a separate account. You can also deduct bank costs for the business account from your income for the business.
