Sync is Easy to Build.
Hard to Keep Working.
Contact and calendar sync between Microsoft 365, CRM systems, and mobile devices is buildable in-house. What it takes to keep it running is the part most teams don’t price in up front.
Why Teams Choose to Buy Instead of Build
The Build Is the Small Part.
Keeping It Running Isn’t.
Build Cost
Mapping fields, writing merge logic, and handling errors before anything goes live. Most teams underestimate this stage because it’s finite and visible. It’s the smallest part of the true cost.
Ongoing Maintenance
Someone owns keeping up with the platform changes, monitoring sync, catching duplicates, and digging into logs every time a user reports a problem.
Reliability at Scale
Scripts commonly process one mailbox at a time. Interrupted runs often restart from the top, and failures can be silent until someone notices it at the worst moment.
Security
A home-grown script can be built securely but someone has to design permission scope, audit its access, and keep documentation current as the build changes.
