I would imagine she has paid people to advise her and look after her, but who have done so badly. I think it's mildly misogynistic that we have a thread about Katie Price's money woes when there is not one about Ian Wright, for example, who is not bankrupt, but is on I'm A Celebrity ... because he owes HMRC a truck load of money as a result - guess what - of being exploited by people who were supposedly giving him good financial advice. Or, indeed, threads about Chris Sutton, Brad Friedel, John Arne Riise, David James - or any other of the 40% of footballers who declare themselves bankrupt after they finish playing - almost always because they took bad advice.
I do recall an interview with her once - probably in Loaded or FHM in the mid 90s - where she claimed she was on her way to becoming a billionaire, and wondering if she knew how large a number a billion is. I suspect that even given her loss of earning potential over the years, she could still command enough of a fee for events that she could start from nothing and earn enough in the next 2 years to live a nice life and save for the kind of retirement I aspire to - but whether or not will be enough for someone used to much more, I don't know.