Fed up with this twisters:(

Yeah I'm fed up with these twister translation companies:(
It's 7 years I'm doing freelance translations.In fact I'm lucky comparing with some of my other victim friends who are getting cheated regularly.I have been cheated 3-4 times up to now.Of course without counting small cheaters .
When I first started working as a freelance translator , I suffered some times because of my lack of experience.Translation companies would send me a 2 pages long"proof" translation text!
Hell , how can a proof text be so long? This is just pure cheating!
One of them pushed it too far by re-calling me and asking me to do extra 10 sentences of the proof text.I told them I had already done my proof text , but they beseeched me so desperately and I was too lazy to say them no , so I just translated that damn text.But you know , there are some people who are really cheeky.These pretending-to-be-smart-ass people called me back the other day saying they'd forgotten to give me yesterday another paragraph of that proof text.
Well , it was that moment that I freaked out, I told them I had already done the proof text and that they should find another fool to collaborate with , as I didn't want any longer to collaborate with them!
You know? This worked! We're collaborating now successfully for these 4 last years!:)
But alas, not all of them are like this.
Now it's exactly 10 months I'm waiting for a 175 € of payment from a disgusting translation company.I have never faced with such people in my life!Maybe a disadvantage of working as a freelance translator is starting collaboration without meeting with the translations company people.In fact I can do this , but you know I don't prefer too as far as I have my money deposited.Why lose time? But maybe I should do it from now on:(
In fact big translation sites such as translatorscafe.com,proz.com etc are doing a great job in their warning forums, but you know worms are slippery and they somehow manage to survive and alas , cheat many people.
The thing that saddens me more , is that while doing this damn translation, I had my daddy and mommy with me.I lost 5 hours with this damn text , where I could have passed much more time with my parents!:(
It is for that special reason that hurts me this much.I called these monsters and each time they'd say me different lies, they'd show me different excuses and they'd promise me each time they'd make the payment by the end of that week.I spoke to them very harshly , offended them, accused them, threated them I'd tell everything to their clients and they wouldn't be able to get any other project, but unfortunately all of these resulted useless.
I called them some days before and they kept talking and smiling promising me they'd do the payment by the end of that week:( I'm tired of dealing with them, I mean how can people get so abased?The last thing I'm planing is visiting them suddenly and ask for my money , threating them.But maybe I shouldn't go alone there , as you can expect everything from this disgused guerrillas:(
What do you guys suggest?