Newbie here, would first like to say a big thanks to the peeps who run the show - I too read the MSE article and having looked through the forum and the FAQs have been most impressed.
We banked with the Halifax for many years and found ourselves in financial difficulty about 2 - 3 years ago. Account charges were a common feature back then, and they often left us chasing our tails in a fairly vicious circle. For some reason, we have always kept our bank statements (4 years worth) so I had a look back... £1,292 in charges!! I have used the spreadsheet to work out interest (an e