But they can't collect commissions on them.

NOTE: that's assuming the IAR is not dually-registered is a RegRep.

Thanks. 

Are you really talking administration or are you considering advising?  Administration is usually done by a broker with back-end systems, like Fidelity or Vanguard.  I believe this requires a lot of infrastructure to be compliant and margins are extremely thin.  Advisory work can be done without the overhead on a fee basis that is either fixed or dependent on the AUM.