I think it depends on what "complete integration" means from a list-based approach or what all they're trying to integrate. And also - what level of the integration you're trying to solve.
For example: if you were trying to solve just the endpoint problem (getting data in and out of Sage 100), there are options. My team sells a "Sage 100 REST API" that lets you get data in and out of Sage 100 via a modern interface. Kissinger has their own brand of Sage 100 REST API as well, and you'll find that there are at least 3-4 other solutions that can help solve the endpoint problem.
Other example: if you are trying to solve the process of pushing/pulling data between the two systems, you'll want more of an iPaaS solution that allows you to define the flow of data from one system to another. In that case, you're looking for something like Starfish ETL or a similar program that has pre-defined endpoints to both sides of the equation AND has an orchestration layer.
Last example: if you're trying to solve a turnkey solution that perfectly melds both systems together... π¬ I'm not sure that exists, and if it does, it's likely been built around someone else's use case.
I know that's the equivalent of talking in circles, but I hope something in there helps or at the very least refines the request. I've solved lots of these scenarios where it's very much a situation where you're trying to get data in and out of Sage 100 with another SaaS solution (Zoho, Salesforce, logistics platforms, etc.), and the thing that needs to be solved is never the same. If any of this stirred additional considerations or questions, I'm happy to help where I can!
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Best Regards,
Basil Malik
CEO and Founder
e:
basil@malik-inc.com------------------------------