Ray Boulger, at mortgage broker John Charcol, said he would expect any fall in lending to be modest. "As a result of many mainstream lenders' tighter criteria we are transacting increasing amounts of business with private banks and other niche lenders, often at better rates than are available on the high street, and we don't expect their appetite to diminish," he said.  Mortgage availability has been improving and there is even a mortgage available for those with just a 5pc deposit. Skipton Building Society is offering a first-time buyer's mortgage fixed at 6.99pc for two years. Those with a 10pc deposit can currently get a mortgage at just under 5pc, fixed for two years, with the Co-op and Britannia.  Borrowers with bigger deposits can fix their mortgage for up to 10 years, with rates at 4.99pc from Yorkshire Building Society.  It is difficult to predict what will happen to interest rates, and the rates that might be available if mortgage lending tightens. At present, many borrowers, including those with Nationwide and Lloyds, are on their lender's standard variable rate (SVR), enjoying paying as little as 2.5pc on borrowings. For those who are looking to fix soon, Melanie Bien, from mortgage brokers Private Finance, warned that the best fixed rates might not stay on the market for long. But home owners should do the maths before deciding whether to fix their mortgages, since, for many people on low SVRs, rates would have to rise a long way quickly for them to lose out.  Ms Bien calculated that a customer with a £150,000 Nationwide mortgage on a standard variable rate of 2.5pc would pay £18,750 over a five-year period, while if they remortgaged to Co-op's deal at 4.19pc they would pay £31,425 over the same period. If interest rates rose by half a point this time next year, assuming no further rate rises, the Nationwide mortgage would still be £9,675 cheaper over the period. If the Bank Rate rose by half a point in July next year, again in May 2012 and then again in May 2013 to stand at 2.5pc, the Nationwide mortgage would still be £3,000 cheaper over the period.  If Britain does enter a double-dip recession then the likelihood is that rates will stay low for the foreseeable future – any sharp rise would hold back an economic recovery.  Ed Stansfield, of Capital Economics, said interest rates could be kept at current levels until the end of 2011, while the Royal Institution of Chartered Surveyors is also predicting long-term low rates.  Gilt specialist David Kauders even suggested that interest rates would stay at about 0.5pc for 10 or 20 years. "The high interest rates we've had for the past 30 or 40 years have been an aberration – for centuries rates were about 2pc and there was no inflation. The aberration is now over, but we haven't realised it yet."  Their views may be cheering for people with tracker mortgages or paying their lender's SVR, but, for those who cannot afford the economists to be wrong, Mark Harris of Savills Private Finance said: "As a rule of thumb, I would say fixing for five years at 4pc looks great value but two-year fixes at 2.79pc are maybe not so great. Remember that fixed fees work better on large loans, percentage fees are better on smaller loans. Clearly, fees on a five-year fixed rate work out cheaper on an annualised basis."  Some of the best five-year fixed rates include 4.19pc from Britannia and the Co-op, available to those with a 25pc deposit or equity in their home, with a fee of £995. First Direct offers a similar rate with a £99 fee, but it is available only to those with a 35pc deposit. If you have just a 10pc deposit, you can fix at 5.2pc for five years with the Co-op, paying a fee of £500.  John Charcol launched a new solution for borrowers with larger mortgages on tracker or standard rates this week. The company is allowing customers to buy a ''cap'' against inflation if they have a mortgage of at least £500,000.  A five-year cap to cover a £500,000 mortgage currently costs about £16,500 for a cap at a Bank Rate of 3pc, £13,500 for a cap at 4pc and £11,500 for a cap at 5pc. Mr Boulger said that, although these caps look expensive, they will often work out cheaper than the traditional market alternative. They are also available to buy-to-let investors whose portfolio of mortgages may be tracking the Libor rate, and those who are unable to remortgage because of a lack of equity.  "Unless you are the proud owner of a crystal ball, knowing what the future for interest rates looks like is all but impossible. What we do know, however, is that we are in challenging times with plenty of unknowns," Mr Boulger said.  Find mortgage deals with Telegraph Mortgage Finder
Talk of double-dip recession is alarming many who are hoping to get a    mortgage, while the slowdown in house prices is a concern for home owners    looking to move.