When adding or editing an account there is an option to define an account as being "Mostly Personal" or "Mostly Business". Cheqbook uses this setting when autocategorizing downloaded transactions. If an account is mostly business, it will autocategorize to business accounts from the Chart of Accounts. If the account is set to mostly personal, it will autocategorize to the equivalent personal account. For example, a Costco transaction under "Mostly Business" might be categorized as "Meals and Entertainment". Under "Mostly Personal", it might be "Personal - Groceries".
It is common for business owners to use the same credit card for both personal and business transactions. If we say an account is "Mostly Personal" that means it will autocategorize all those transactions as personal by default. This saves time as you only need to pick out the rare business transactions to recode. Personal transactions are listed seperately in the Balance Sheet report. The inverse is also true. If you occasionally have personal transactions on a business account, you can recode those transactions to their personal equivalent.