If im being honest, I'm not going to miss £500-600, not to say it wouldn't help though. The reality is that there's not much to lose, except from £60 if it goes to small claims court and fails, and obviously a bit of time but that's no bother. Hes being a willy, not paying what is owed and that pisses me off more than anything else. I don't work purely for the money, I work to enjoy it more than anything else but obviously money is important and theres a significant amount which he's pocketing. If I don't get this money, my total lost amount of money will probably come close to around £1300-1500 between 3-4 farmersI'd probably just walk away at this point. Your time and energy is probably better put to use in your new job. And sooner or later he's going to get hacked off with you pushing him, and he may turn out to be the vindictive type...
Chalk it down to experience, learn what you can from it and move on.
Happy new year; make it a good one.
(Easy for me to say. I'm not the one who feels hard done by...)