In the past, the only type of buy to let mortgages available were variable rate deals. However, nowadays there is a whole range of buy to let mortgages, from fixed rates and discounts to trackers and flexible rate mortgages.

Buy to let mortgage lenders will usually insist that you have a deposit of 15 per cent, so the size of your deposit will help determine the amount you can borrow. Lenders will usually insist that the rent the property will command covers 125 per cent of your mortgage payments (although some will accept 100%).

This protects both you and the lender against rental voids - periods when the property is un-tenanted.

Unlike residential borrowers, most buy to let investors opt for interest-only mortgages, simply paying off the interest owed to the lender, but not the outstanding capital. This is repaid on the sale of the property.