If I am using a system such as CCH iFirm client as well as Xero Tax, can I integrate FYI with the Xero Tax client database?

Yes, wherever the practice is using Xero Tax then FYI can be seamlessly integrated with the practices client database. This is possible because behind the scenes Xero Tax is simply Xero Practice Manager, with the Xero Practice Manager functionality hidden. Behind the scenes the jobs are still being generated.

In order to integrate in this scenario you will need to get the FYI app key from Xero Tax/Xero Practice Manager under Business - Settings - Add-ons.