The number of people buying property as an investment has ballooned over the last decade. But you can't just buy a property with a normal mortgage and start renting it out - letting your property is usually against the terms of your mortgage agreement. Lenders take a dim view of people who let out their property without permission and can even end up serving you notice on the property.

Buy to let is a joint initiative that was originally set up by ARLA and a small panel of mortgage lenders to help individuals invest in the residential property market without having to pay commercial rates of interest on their mortgage.

Whilst the comparative robustness of the residential property market is the main driving force behind the increase in the popularity of this type of investment, there is no doubt that the improvements to the buy to let mortgage products available on the market have also been an important factor.

There are now around 70 lenders offering range of deals that now include discounted, fixed, variable, tracker, flexible and even self certification mortgages, helping to make buy to let an investment that is accessible to a broader section of the population.

One of the key things to remember is that buy to let should not been seen as a short term option, but if you research, plan and manage your investment correctly, you should end up making a profit in the medium to long term. It is not without its risks and involves considerable initial and ongoing costs including lettings agent commission, management fees, tax, insurance, legal cover, maintenance and repairs, service charges, and ground rent.