looking through some paperwork yesterday i found a letter from about 2 years ago which offered me a mortgage of 125% of the value of the property or 5.9 times my annual salary
the letter i got yesterday said i could remortgage if it was less than 60% of the vaule of the property

most mortgages will let you overpay by 10% without a penalty per year, then you get hit with 3% or so if you overpay, so unless you have a big windfall and can take the hit of 3% it's better to save up the cash and, when you remortgage, pay the lump sum off in one hit and get the mortgage down a bit too
£17k is 10% for me this year, might do it, might nt, recent rate cuts have seen the mortgage drop by £150 a month over the year so i'm happy