The Waiting on column names the party whose action advances the application, with what is required of them underneath — for example, Tenant over "Service fee", or The Student Guarantor over "Identity documents under review".
The parties are:
Tenant — the application, service fee, identity check or signature is with them.
Cosigner — identity verification or signature is with the cosigner.
You — an action sits with your company, usually confirming rent details; the application also appears under Action required.
Letting agent or Landlord — the confirmation of rent details has been requested from the tenancy manager outside your company.
The Student Guarantor — a check or review is in progress; no partner action is required.
Use the column to decide whether to chase. Rows waiting on the tenant or cosigner are candidates for a nudge; rows waiting on The Student Guarantor are being worked through and need nothing from your company.
Rows under Attention required always carry the specific reason — a rent that does not match the offer, an invitation that was not delivered, an application that has gone dormant — so the queue can be triaged without opening each row.