That's all and fine - people should pay a flat fee to access...

That's all and fine - people should pay a flat fee to access that 'expertise' so that other people who aren't using a broker aren't subsidizing the trail.

Either that or  the broker charges a trail commission on top of the carded loan rate which their client pays. ie if the bank's loan is 4%pa and the broker wants 15bps, then the client should pay 4.15%pa.  this is what happens in the term deposit market with say TAU who if a bank is offering a term deposit at 3%pa, TAU will offer it to the client at 2.95%pa and they keep the 5bps as brokerage.