1. Everything in Simple Start and Essentials. Invoicing, expense tracking, bill pay, basic reports, receipt capture, and time tracking all carry over; Plus builds on top of them rather than replacing anything.
2. Inventory tracking. This is the headline feature. Plus tracks quantity on hand, cost, and automatically adjusts your books as you buy and sell inventory items, something neither Simple Start nor Essentials supports.
3. Project profitability. You can tag income and expenses to a specific project and see, in one report, whether that project actually made money, rather than piecing it together from the general ledger.
4. Budgeting tools. Plus lets you build budgets by account, by class, or by location and compare actuals against them, which isn't available on the lower tiers.
5. Class and location tracking. You can tag transactions by department, location, or any other category you define, then run reports split by those tags. Useful for a business with multiple locations or revenue streams that wants to compare them side by side.
6. Up to five users. Essentials caps at three; Plus allows five, plus a couple of additional accountant-only seats that don't count against the limit.