The honest version of "does it integrate with my software." These are the systems this industry actually runs on, and what each one means for a build.
Lacerte / UltraTax / Drake / ProConnectTax preparation
The production system. Integration is generally limited and version-bound, so most agents work alongside it — on the intake and review sides — rather than inside it.
Karbon / Canopy / JetpackPractice management
Where jobs, deadlines, client tasks and internal workflow live. The natural anchor for anything about status, chasing or assignment, and generally the most integration-friendly system in the stack.
QuickBooks Online / XeroClient bookkeeping
Where write-up and advisory clients' books live, usually across dozens of separate client files. Well documented and straightforward to read across a portfolio.
Client portal and document collectionDocument intake
SmartVault, Liscio, TaxCaddy or the portal built into practice management. The chase for missing documents is the single largest recurring administrative cost in a tax practice.
Document managementFiles
Where prior year workpapers, engagement letters and permanent files live. Frequently a folder convention rather than a structured system, which is workable but needs the convention explained.
E-signatureEngagement and authorizations
Engagement letters, e-file authorizations, and the chase for signatures that hold up filing.
Time and billingRevenue
Either inside practice management or separate. Realization by client and by job is the number most firms want and few produce without effort.
Bank and payroll feedsData sources
Transaction and payroll data flowing into client files, with the coding and exception handling that follows.
EmailClient communication
Where the vast majority of client work actually arrives, including documents that should have gone to the portal.