I have been with my bank for over 10 years, my partner for a similar length of time. The local branch operated a scheme where staff came to my school on Fridays to allow us to open accounts. I suspect it was designed to ensnare us while young to build loyalty, and it certainly worked in my case.

So it was without a second's hesitation that we decided to approach our good old bank for a mortgage. In late 2006 we entered a branch, had a chat and came away with an agreement in principle (AIP) for a mortgage. For those not in the know, an AIP is the amount of loan the bank will agree to extend to you, although it is not a binding contract. It wouldn't exactly buy us a mansion, but our financial situation was changing for the better and we were confident the bank would up their offer when we were ready to buy a house.

I feel I should note here that the woman who gave us the AIP was fully aware of our employment and financial situations. I am an IT contractor working through my own company and my partner is freshly on the job ladder out of University.

Fast forward to January 2007, back home after Christmas with the families. Our thoughts turned once again to buying a house and we began browsing for properties in the area. One stood out: a pleasant semi in easy walk of the city centre that was well within our price range.

After some consideration we decided to approach our bank and see what they would offer. My partner rang their mortgage centre, explained the situation and was told that the bank would indeed be able to help and we were to expect some documents to check and sign within two days.

Excited with our mortgage secured, we contacted the estate agent to put in an offer which was accepted after a little negotiation. Things were looking up!

However, two days came and went, so we put in another call to the mortgage centre. It seemed they had no record of our previous conversation, so we spent another hour on the telephone giving details. Again, we were to expect some documents very soon.

True to their word (at least the second time) a large wad of paper arrived by post. Immediately we could see that several important details were incorrect, most importantly the loan amount. Unimpressed, we proceeded to the local branch of the bank and asked to speak to someone about lodging a proper application only to be informed that nobody could help us; we were instead to go to the city centre branch. One hour and two members of staff later, we had an appointment to see a "proper" mortgage adviser the following week.

The first meeting went well and we had two offers from which to choose. Instead of applying there and then we were to spend a couple of days thinking it over, so we arranged to meet again later in the week.

At the next meeting our dream was shattered. Owning more than 33% of a company, the bank considered me self-employed and without three years of certified accounts, there was nothing they could do for me. The previous several weeks had been completely wasted chasing a mortgage that would never have been approved in the end.

You may be wondering, just as we were, how this simple observation managed to evade every single other bank employee who had full knowledge of our circumstances. Our mortgage advisor didn't know either, but promised to investigate.

Now, one month later, we have found a lender who accepts that not everyone conforms to the traditional employment model and the purchase of the house is very much in motion. Things are once again looking up! We have heard nothing from the investigation into the mortgage centre, but I really do not expect to.

I'm not going to name any of the parties involved in this sorry saga, but I expect a lot of high street banks operate the same policy. The same level of ineptitude, however, I am not so sure.

Rather than feel defeated, I've chosen to learn some important lessons that I wish I had known in the first instance.

* If you aren't employed in the traditional sense and you can't provide at least three years of certified company and personal accounts, do not expect a high street bank to help you. Instead, you can try approaching a specialist broker as we did.

* Resist the urge to make an offer on a house until you are absolutely certain your mortgage offer is secure.