Event organisers that don't pay!

What novel ways are there to getting paid by event (Training) organisers (other than taking the legal route)

During the past six months, two of my clients, both based in Cape Town, and both advertising in these forums, have not paid my invioces.

First client asked me to assess a few portfolios. On receiving the portfolios, there was no assessor's guide, no notional hours matrix, nothing. When I queried this, I eventually received an assessment guide that only vaguely resembled the contents of the portfolios. The portfolios were also over a year old!

I queried this with  the training provider, and after much to-and-fro, asked them to collect their portfolios. as they were un-assessable.

I invoiced them for two hours work, which is far less time than I spent on this exercise. I am still waiting for payment!

Second case:

Training provider asks me to run a training workshop JoBurg. After the event, i send them an invoice based on an agreement with a previous director, who had since left the oragnisation.

In return, I received a mail from the owner, requesting me to reduce the invoiced amount by 30%, with a veiled threat of no further work.

I offered to give them a 10% discount. In reply,  they  cancelled all further bookings with me!

Reminders of  amounts due remain unanswered.

A substantial amount of money (for me,as a pensioner) is involved, and it would appear that I will have to consult with my attorney on this one.

Any ideas on how to get them to pay, without having to take legal steps against them?