Calculation returning name from Id

I am looking for the best way to automate relationships when importing data. 

Ex. Tenant and Unit data is imported into Podio periodically. The Tenant data has a unitId column. I want a calculation or flow that will take the two matching unitId's in each app and assign the relationship for me. 

My plan is to have a calculation that searches the unitId and returns the unit address, followed by a Globiflow that searches and assigns the relationship. Any help with this calculation or better approach is greatly appreciated.