Investigate missold PPI on defaulted loan?

Cakes2011

Hi there, I'm new to forums so hopefully I'll get this right ...

I've had many consolidation loans / credit cards over the years, and have no idea how much I have been charged for insurance whilst using them. I can't put my hands on paperwork for any of them so following Martin's advice, I've obtained a credit report and am contacting the various credit card companies for my details so I can get the ball rolling to see if I have a case at all. I do recall paying PPI on some of them and being given the hard sell to take it, even though it dramatically increased my payments ... therefore decreasing my ability to meet the payments, which led to my financial crisis!

My main question is about a loan with NatWest bank. I've had many consolidation loans with NatWest, the final one being in default. I sought advice from CCCS (really helpful) after being made redundant while on maternity leave. I followed all their advice, but NatWest didn't want to know about helping me and sold the debt to their own collection company (Triton). An arrangement to pay Triton was set up. However this is now showing as defaulted as Triton sold my debt to another company, Apex, (who began HOUNDING me endlessly for weeks!) and when I requested my original loan agreement from them, I haven't heard from them since.

Having read lots of press on missold PPI etc, I wonder if its worth investigating my many loans / credit cards with NatWest to see what exactly I was paying for as it all arranged over the phone (apart from the very first one) and I have nothing in paper in front of me.

But I don't have any paperwork or have any idea to where to start ... or even if I should start? I can see from my credit report, my final (and defaulted loan) resulted in my paying an additional £11K on top of the borrowed amount and I would like to know what was for ...

Can anyone offer any advice - really would appreciate it.

Thank you so much