Thanks for the advice. It seems as though keeping business entities separate for tax-time reporting is more about proper "tagging" of individual transactions, than how I categorize accounts (personal vs business vs rental). So, I am keeping my wholly owned business entities and self-employment businesses in a single Quicken file with my personal accounts and ensuring all transactions are tagged appropriately. I did create a separate Quicken file to track a partnership business. So far this approach seems to be working well, although a bit of effort was required to initially tag all 2018 transactions to the right business. I actually had to do something similar in MS-Money, using a custom "Classification" tag. So far I like Quicken and it's nice to be back on an actively developed and supported accounting software.