I think mortgage lenders have clamped down on the x salary they will lend now, so for exapmle, if a bank used to lend 4x joint income, you will find that they may only lend 3x joint income now, and there's no getting round it.
Mortgage advisers can have a level of discretion, but when I was selling mortgages, my level was only about £5K
You may find a mortgage provider who will lend you more, but they will charge a higher rate for it as you would be classed as a higher risk
Sorry, not what you wanted to hear, you'll have to either save more or haggle the price down, or find another property 