From my perspective this is a hypothetical question, as I only have three clients, and I do bookkeeping for them on VT.
However, I am looking to move to an online product (currently looking at QBOL, or Xero), or at least be ready if I pick up another client or so.
I can see that the relationship can be either 'client pays' or 'practice pays'.
I presume, if the client pays, he then provides the agent with some client of authorisation code to permit them access - which he then withdraws at a future date if he moves on.
If the practice pays, what happens when the client wishes to move on?
Also, if the practice pays and the client ceases to trade - presumably the client needs to take on payment in order to retain access to any historical records for the next X years - or do you instead to a massive printout job at that time?